12th Physics Class 12th Physics All Chapter MCQ Test 2026 33 12th Physics Chapter 1 MCQ Test तैयारी में दम हैं तो 25 में से 23 सही करों। 1 / 25 Which of the laws given the force between two charges at rest Gauss theorem Kirchhoff's law Coulomb's law Faraday's law 2 / 25 There are two identical spheres A and B. A is given + Q charge and b is given - Q charge Mass of A increases Mass of B increases No effect on mass None of these 3 / 25 If a sphere of bad conductor is given charge then it is distributed on Surface Surface and also inside the surface Only inside the surface None of these 4 / 25 The force acting on Per unit charge is called Electric current Electric potential Electric field Electric space 5 / 25 Which of the following has unit volt / metre? Electric flux Electric potential Electric capacity Electric field 6 / 25 Van De graaff generator is an electrostatic machine which produces Only high current Only high voltage High current and high voltage Low current and low voltage 7 / 25 The total charge on an electric dipole is Zero negative Positive Infinite 8 / 25 Electric field lines provide information about Field strength Direction Nature of charge All of these 9 / 25 The ratio of electric flux density and electric field intensity is known as Gravitational constant Dielectric constant Both A and B None of these 10 / 25 Voltmeter measures Resistance Potential difference Current None of these 11 / 25 Plastic rod rubbed with fur and glass rod rubbed with silk Repel each other Mix up with each other Attract each other None of these 12 / 25 There are two identical spheres A and B .A is given +Q charge and b is given - Q charge Mass of A increases Mass of B increases No effect on mass None of these 13 / 25 Positively charge body has Excess of electron Deficit of electrons Excess of protons Deficit of proton 14 / 25 A surface enclosis and electric dipole the total electric flux over the surface is Infinite Zero Q None 15 / 25 Force between two charged particle situated at a distance is F. If distance between the two is made half, then the value of electric force will be 4F 2F 1/4F 1/2F 16 / 25 A positively charge glass rod attract and object . The object must be Negatively charge Neutral Either negatively charge or neutral A magnet 17 / 25 When a body is charged its mass- Increases Decreases Remains same May increase or decrease 18 / 25 Spherical conductor is charged the electric field intensity at its Centre will be Infinite Equal to that at the surface Zero None of these 19 / 25 Debye is a unit of Charge Potential Electric dipole moment None 20 / 25 Which of the following physical quantities is a vector Electric flux Electric potential Electric potential energy Electric intensity 21 / 25 An electric dipole placed in a non uniform electric field experience A force but not a torque A torque but not a force A force and a torque None of these 22 / 25 Quantization of charge indicates that Charge which is a fraction of charge on an electron is not possible Charge cannot be destroyed Charge exist on particles There exist a minimum permissible charge on a particle 23 / 25 The electric field intensity inside of hollow spherical charge conductor is Infinite Zero positive and greater than 1 None of these 24 / 25 SI unit of electric dipole moment is CN Cm C C/m 25 / 25 An electric dipole placed in a uniform electric field experience in general A force and a torque Only a force Only a torque None of these Your score isThe average score is 39% 0% Restart quiz 9 12th Physics Chapter 2 MCQ Test तैयारी में दम है तो 37 में से 35 सही करके दिखाओं। 1 / 37 The net charge on a charged capacitor is Zero 1 1C Infinite 2 / 37 If the distance between the two charges is increased then the electrostatic potential energy of the charges Decreases Increases May increase or decrease Same 3 / 37 The electric potential inside the charged the hollow sphere is- Zero Uniform Infinite None of these 4 / 37 When a body becomes negatively charged , its mass Decreases Increases Remains the same None of these 5 / 37 When a medium of dielectric constant k fills the gap between the plates of a capacitor its capacitance compared to air filled state- Increases K times Decreases K times Both None 6 / 37 If an earthed conductor is brought near an insulated conductor then the capacity of insulated conductor? Decreases Increases Remains unchanged None 7 / 37 The dielectric constant of water is- 1 60 80 40 8 / 37 If a dielectric slab is introduced in between the two plates of capacitor then its capacitance Increases Decreases Remain same Becomes zero 9 / 37 Eight drops each of radius r and charge q of are merged to form a single drop . the ratio of the potential of big dropped to a small drop is 8:1 4:1 2:1 1:8 10 / 37 Electric potential of earth is taken to be zero because the earth is good Semiconductor Conductor Insulator None of these 11 / 37 Three condenser each of capacity C are connected in the series then there equivalent capacity will be 3C 3 C/3 1 12 / 37 Linear charge density is equal to Charge/surface area Charge/length Charge/volume None of these 13 / 37 The dielectric constant of water is 80 60 40 20 14 / 37 If a proton is brought near another proten then its potential energy- Increases Decreases Unchanged None 15 / 37 Which are the following value of n is not possible in relation Q= ne? 4 8 2 4.2 16 / 37 A point charge q is rotated around another point charge Q in a circular path work done by electric field on it will be Zero Positive Negative None 17 / 37 Electric potential at the centre of a charged hollow metal sphere is Zero Twice at that on the surface Half of that on the surface Same as that on the surface 18 / 37 The capacitance of a parallel plate capacitor by the introduction of a dielectric between the plates of the capacitor. Increases Decreases Remain same Nothing can be said 19 / 37 A dielectric constant 6 is to be filled in the gap between plates of a parallel plate capacitor. what is the factor by which the gap should be changed to maintain the same capacitance? 6 times 1/6times No change None of these 20 / 37 The electric dipole moment per unit volume of a dielectric medium is called Polarization vector Electric flux Displacement Distance 21 / 37 Two capacitor each of capacity C are connected in parallel .The equivalent capacity is 2C C C/2 1 22 / 37 Dielectric constant for vacuum is 1 Infinity 2.3 4.7 23 / 37 If a dielectric is placed between two plates of a parallel plate capacitor, the value of capacitance- Increases Remains constant Decreases None of these 24 / 37 In a region of constant potential The electric field is uniform The electric field is zero The electric field is infinite None of the 25 / 37 The work done by electric field on a charged taken from one point to another of an equipotential surface will be Positive Negative Zero None of these 26 / 37 Potential gradient is equal to dx/dv dx.dv dv/dx None 27 / 37 The loss of energy taking place due to sharing of charge between two conductors depends upon Potential difference Square of potential difference Capacitance Square of current 28 / 37 Sum of charges on collecting and conducting plate of a charged capacitor is- Zero 1 Infinite 50 29 / 37 The capacitance of a spherical capacitor is directly proportional to its Radius 1 0 None 30 / 37 The value of electric field inside a charge is spherical conductor is Q Zero E π 31 / 37 When I show bubble is charged its radius will Increases Decreases Remains the same Because zero 32 / 37 Van de graff generator is used for producing High current High voltage High power High capacity 33 / 37 The value of electric potential at a distance r from a point charge is Proportional to r Inversely proportional to r Proportional to r square Inversely proportional to r square 34 / 37 Three condenser of equal capacity C are connected first in parallel and then in series .the ratio of equivalent capacity in both conditions is- 9:1 6:1 3:1 1:9 35 / 37 The capacity of any conductor is C=qv C=v/q C=1/2qv C=q/v 36 / 37 The electric potential due to electric dipole at the point lies on the bisector of its axis is- 1 Zero Infinite 100 37 / 37 An electron of charged e coulomb passes through a potential difference of V volt its energy in joule will be V eV e ve Your score isThe average score is 64% 0% Restart quiz 5 12th Physics Chapter 3 MCQ Test तैयारी में दम है तो 35 में से 33 सही करके दिखाओं। 1 / 35 Electric current is a Vector quantity Scalar quantity Tensor None of these 2 / 35 Electric current is a scalar quantity because It obey the law of vector addition It does not obey loss of vector addition It obey The law of inertia None of these 3 / 35 Which of the following is the best conductor of electricity? Silver Gold Aluminium Zinc 4 / 35 As the temperature rises the resistance offered by metals Increases Decreases Remain same None of these 5 / 35 The spacific resistance of a conductor increases with- Increase of temperature Increase of cross sectional area Decrease in length Decrease of cross sectional area 6 / 35 Which of the following is the same in parallel connection of resistances? Potential difference Current Both potential difference and current None of these 7 / 35 The value of yellow colour in colour code of carbon resistance is 1 3 4 8 8 / 35 Amphere hour is unit of Power Charge Energy Potential difference 9 / 35 Electric current density is a Vector quantity Scalar quantity Both None of these 10 / 35 Kilowatt-hour is unit of Electric power Electric energy Torque Electric current 11 / 35 Which law follows the law of conservation of energy Lenz's law Kirchhoff's law Maxwell law None 12 / 35 The resistivity of material of a conductor depends on Length Cross sectional area Temperature None of these 13 / 35 The algebraic sum of all current meeting at any point in an electrical circuit is Infinite Positive Negative Zero 14 / 35 Which of the following is conserved is kirchhoff's law? Energy Force Charge Potential 15 / 35 Amphere is equal to Joule/second Coulomb/second Volt/coulomb Joule/coulomb 16 / 35 Which one is correct? Current is a scalar and current density is a vector Current is the vector and current density is scalar Both the quantities are vectors None of these 17 / 35 Ohm's law is followed by Conductor Semiconductor Insulator All of these 18 / 35 Ohm's law is valid when the temperature of conductor is Very low Very high Different Constant 19 / 35 The length of wire is doubled its conductance will be Remains unchanged Halved Double None of these 20 / 35 Value of green colour code on carbon resistance is 3 4 5 6 21 / 35 On cooling the resistivity of metals Increases Decreases Both None 22 / 35 The electrical appliances in our houses are connected across supply switch in Series Parallel Mixed grouping None of these 23 / 35 Unit of electromotive force is Newton Joule Volt Metre 24 / 35 Wheatstone bridge is used in the measurement of E.m.f Current Resistance Charge 25 / 35 The length of wire is doubled its conductance will be Remains unchanged Halved Double None of these 26 / 35 The equivalent resistance of resistor in parallel combination Increases Decreases Remain same None of these 27 / 35 Kirchhoff's junction rule is based on conversation of Mass Charge Energy All 28 / 35 Colour code of carbon resistance for blue colour is 4 3 8 6 29 / 35 Colour code of carbon resistance for white is 5 6 8 9 30 / 35 The motion of electron inside the conductor is Uniform Accelerated Drifting Decelerated 31 / 35 Kirchhoff's loop rule is based on conservation of Mass Charge Energy None of these 32 / 35 The value of red colour in colour code of carbon resistance is 0 4 2 8 33 / 35 Specific resistance for a wire depends upon Length Cross section area Mass None of these 34 / 35 What is mainly measured by potentiometer? Current Resistance Potential difference All of these 35 / 35 Wheatstone bridge compares Resistances Current Potential difference All of these Your score isThe average score is 49% 0% Restart quiz 12th Physics Chapter 4 MCQ Test तैयारी में दम है तो 35 में से 33 सही करके दिखाओं। 1 / 35 Voltage sensitivity of a voltmeter is- NBA/CR NBA/C NBA C 2 / 35 The force between two moving charges is Only coulomb force Both magnetic force and electric force Nuclear force None of these 3 / 35 The S.I. unit of magnetic field or magnetic induction is Tesla Weber Henry Newton 4 / 35 A charged particle moves perpendicular to a magnetic field It's momentum and kinetic energy are constant It's kinetic energy changes but its momentum is constant It's momentum changes but kinetic energy is constant None of these 5 / 35 Which are the following relation between 'G' the resistance of galvanometer and V the resistance of voltmeter is correct? V>G G>V Both None 6 / 35 The magnetic field due to a long solenoid is Directly proportional to N Directly proportional to N square Inversely proportional to N Independence of N 7 / 35 Tesla is unit of ? Electric flux Magnetic flux Magnetic field Electric field 8 / 35 For two magnetic force field tangent law holds good when the angle between them is- 45° 90° 0° 180° 9 / 35 Gauss is a unit of Magnetic field Magnetic induction Both A and B None of these 10 / 35 A charge moving with uniform velocity produces- Only an electric field Only a magnetic field Electromagnetic field None of these 11 / 35 On using shunt , the sensitivity of galvanometer- Decreases Increases No change None of these 12 / 35 When and ammeter is shunted its total resistance in the circuit Increases Decreases Remains unchanged None of these 13 / 35 The resistance of ammeter is Very small Very large Extra small Extra large 14 / 35 The resistance of a galvanometer is Deep a current of 1% (or 1/100 part) of main current will pass through it if the shunt is G/100 G/99 G/67 G77 15 / 35 When an ammeter is shunted , it's measuring range Increases Decreases Remains constant None of these 16 / 35 The radius of a circular current loop is made double and the current is made half. the magnetic moment of the loop will become Halved Doubled Four times large None of these 17 / 35 The law , governing the force acting between two electric charges known as Ampere's law Ohm's law Faraday's law Coulomb's law 18 / 35 Current sensitivity of a moving coil galvanometer is NBA/CR NBA/C NBA None of these 19 / 35 Current sensitivity depends on Number of turns Strength of magnetic field Area of coil All of above 20 / 35 Magnetic field due to a toroidal solenoid is independent of Its number of turns Electric current Radius None of these 21 / 35 Current in two parallel wires are directed opposite to each other. These wires Repel each other Attract wach other Exert no force on each other Destroy the currents of each other 22 / 35 If the current in an ideal solenoid be doubled , the magnitude of magnetic induction at a point in the solenoid will Get doubled Remain the same Both None of these 23 / 35 A charged particle is given a motion along the magnitude field line . The force acting on the particle will be In the direction of velocity In a direction opposite to velocity Perpendicular to velocity Zero 24 / 35 Current sensitivity of a moving coil galvanometer can be increased by Increasing the number of turns Increasing the magnetic field Increasing the area of coil All of above 25 / 35 A charged particle is released from rest in a combined parallel electric and magnetic fields the motion will be In a straight line In a circle In a helix In rectangle 26 / 35 A circular coil of radius r carries a current I. The magnetic field at its centre is B . At what distance from the centre on the axis of the coal the magnetic field will be B/8 √2R √3R 2R 3R 27 / 35 The unit of voltage sensitivity is Rad rad/metre rad/volt None of these 28 / 35 If any ammeter is shunted then the total resistance of the circuit Increases Decreases Remain same None of these 29 / 35 Resistance of ideal ammeter is Infinity Zero 100 ohm 50 ohm 30 / 35 An electron enters perpendicularly to a uniform magnetic field the path of the electron will be Circular Perpendicular Linear Spiral 31 / 35 Where are charged particle enters a magnetic field, its kinetic energy Remains constant Increases Decreases Becomes zero 32 / 35 To parallel conductors carrying current in the same direction will Attract each other Repel each other Both None of these 33 / 35 50 particle enters into a magnetic field at 30° with induction vector. It's path becomes Circular Helical Elliptical Line 34 / 35 In a vertical wire current flows from lower to upper. If an electron beam is sent horizontally towards wire than deflection will be Right side Upward Downward Left side 35 / 35 If a current is passed through spring the spring will Be stretched Be compressed Remain as it is None of these Your score isThe average score is 46% 0% Restart quiz 3 12th Physics Chapter 5 MCQ Test तैयारी में दम है तो 21 में से 19 सही करके दिखाओं। 1 / 35 At any point on the perpendicular bisector of a bar magnet Magnetic field is zero Magnetic potential is zero Field and Potential both are zero None of these 2 / 35 Which of the following is not a magnetic element of the earth at a place ? Declination Dip Magnetic moment Horizontal component of Earth's magnetic field 3 / 35 If a bar magnet is cut into two parts perpendicular to its length , for one part , which of the following will not change? Pole strength Moment of inertia Magnetic moment Magnetic length 4 / 35 Direction of the magnetic induction at an axial point and magnetic moment of a bar magnet are Parallel Anti parallel Mutually perpendicular None of these 5 / 35 Angle between the Earth's magnetic axis and Earth's geographic axis is about Zero 11° 1 None 6 / 35 The apparent dip at a place is always Greater than true dip Less than true dip Equal to true dip None of these 7 / 35 The angle between the magnetic dipole moment and magnetic induction at the axis of circular current is - 0° π 2 100000 8 / 35 Iron is - Paramagnetic Diamagnetic Ferromagnetic Non magnetic 9 / 35 Nickel is Paramagnetic Diamagnetic Ferromagnetic None of these 10 / 35 The magnetic susceptibility of air is Positive Negative Zero None of these 11 / 35 Liquid and gases are not - Ferromagnetic Diamagnetic Paramagnetic None of these 12 / 35 Copper is - Paramagnetic Ferromagnetic Diamagnetic None of these 13 / 35 Magnetic lines of force of straight current are- Circular around current Straight and parallel to current Both None of these 14 / 35 The value of magnetic susceptibility of vacuum is Equal to 0.5 Infinite 1 Zero 15 / 35 Curie temperature is that below which A ferromagnetic substance become paramagnetic Ferromagnetic substance become diamagnetic Paramagnetic substance become diamagnetic A Ferromagnetic substance remains ferromagnetic 16 / 35 To make an electromagnetic material should have- Higher magnetic susceptibility Higher retentivity Lower attentivity None of these 17 / 35 Ongoing from north pole to equator, the value of angle of dip Remains constant Increases Decreases First decreases and then increases 18 / 35 The value of magnetic force field at the surface of earth is - 0.5 gauss 2 gauss 4 gauss None of these 19 / 35 The resistance of an ideal voltmeter is - Infinite Zero 500000 9 20 / 35 Which pair has the same S.I dimensions? Magnetic field intensity and magnetization Magnetization and susceptibility Susceptibility and permeability None of these 21 / 35 Which quality should be present for making permanent magnet? High coercivity Less coercivity High magnetic retentivity A and C both 22 / 35 When magnetic moment of an oscillating magnet increases, its time period will - Increases Decreases Remains unchanged None of these 23 / 35 The permeability of a ferromagnet Depends upon magnetic field Is independent of magnetic field Is proportional to magnetic field None of these 24 / 35 The angle between magnetic meridian and geographical meridian is called Angle of dip Declination Horizontal component of magnetic field Apparent angle of dip 25 / 35 The angle between the geographic meridian and the magnetic meridian is called Inclination Declination Dip None of these 26 / 35 The origin of magnetism in a magnet is Spin of electron Cosmic rays Presence of a big magnet in the earth The earth 27 / 35 Magnetic dipole moment is a vector quantity directed from: South to North pole North to south pole East to west direction West to east direction 28 / 35 Which of the following will have negative magnetic susceptibility? Paramagnetic Diamagnetic Ferromagnetic None of these 29 / 35 The magnetic moment of a bar magnet is M . It is bent at 60° from middle then magnetic moment will become - M M/3 M/2 None of these 30 / 35 Which of the following has higher magnetic susceptibility Diamagnetic Paramagnetic Ferromagnetic None 31 / 35 Which is more appropriate material for a strong electromagnet? Air Soft iron Steel Allow 32 / 35 The magnetic field is strength of a magnet is the greatest at The centre The poles Infinity None of these 33 / 35 The angle between total field and horizontal field in magnetic meridian at a place is called Declineation Dip Horizontal component of Earth's field None of these 34 / 35 When the intensity of magnetic field is increased four times , the time period of suspended magnetic needle becomes. Double Half Four times One time 35 / 35 In making permanent magnet we use - Steel Copper Soft iron None of these Your score isThe average score is 24% 0% Restart quiz 1 12th Physics Chapter 6 MCQ Test तैयारी में दम है तो 35 में से 33 सही करके दिखाओं। 1 / 35 The principle of mutual induction is used in Transformer Induction coil Both None of these 2 / 35 Direction of Eddy current is obtained from - Kirchhoff's rule Lenz's law Plank's law None of these 3 / 35 Magnetic flux is the Vector quantity Scalar quantity Tensor quantity None of these 4 / 35 Inductance is the Scalar quantity Vector quantity Both a and b None of these 5 / 35 The working of dynamo is based on the principle of Heating effect of current Electromagnetic induction Magnetic induction Electric induction 6 / 35 When the rate of change of current is unity, The induced emf is equal to Thickness of coil Number of turns in coil Coefficient of self inductance Total flux linked with coil 7 / 35 Calculate the magnetic flux when the magnetic field is perpendicular to the surface area . Minimum Maximum Zero Depend on the surface area 8 / 35 To convert mechanical energy into electrical energy are can use DC dynamic AC motor Motor Transformer 9 / 35 An inductor may store energy in its Electric field Magnetic field Both None of these 10 / 35 Which physical quantity has SI unit Henry ? Self inductance Mutual inductance Both None 11 / 35 SI unit of magnetic flux is Weber Watt Tesla Joule 12 / 35 Lenz's law is derived from Kepler's law Newton's law Coulomb's law Faraday's law 13 / 35 SI unit of mutual induction is - Henry Ohm Tesla None of these 14 / 35 A circular coil is held in vertical plane. Bar magnet is taken towards it with north pole towards coil. Direction of current as scene from the side of magnet is Anticlockwise Clockwise First anti clock wise and then clock wise First clockwise and their anti clock wise 15 / 35 Calculate the magnetic flux produced when the magnetic field is parallel to the surface area. Maximum Minimum Zero None of these 16 / 35 Lenz's law is the result of which principle of conservation? Current Energy Momentum Charge 17 / 35 The phenomena called electromagnetic induction was first investigated by Newton Kepler Faraday None of these 18 / 35 The rate of change of magnetic flux in a loop is equal to - emf induced Current induced Electric field induced None of these 19 / 35 If a denial cell is connected across the primary coil, the change in flux in the secondary will be 19 20 Zero None of these 20 / 35 An induction coil gives High voltage at high current High voltage at low current A low voltage at high current A low voltage at low current 21 / 35 Which of the following is consequences of the law of energy conservation? Lenz's law Faraday's law Ampere's law None of these 22 / 35 Instrument which converts mechanical energy into electrical energy is - Induction coil Dynamo Transformer Motor 23 / 35 The law of electromagnetic induction was discovered by Faraday Fleming Lenz Rumkorff 24 / 35 The role of self induction is equivalent to Momentum Force Energy Inertia 25 / 35 When current in a coil changes from 5A to 2A in 0.1s then average voltage of 50V is produced. The self induction of the coal is 1.67 henry 6 henry 3 henry None of these 26 / 35 Magnetic flux per unit area is Magnetic field Magnetic field density Both None of these 27 / 35 The mutual induction of two nearby coins is 1.5 H. If in one of these coils, the current grows from zero to 20A in 0.5s, the flux linked with second qual changes by 10v 9V None of these 30Wb 28 / 35 The relative motion between the magnet and the coil that is responsible for generation of Magnetic field in the coil Current in the coil Voltage in the coil None of these 29 / 35 The SI unit of magnetic flux is Kilogram Weber Second Candela 30 / 35 The working of an induction coil is based on the principle of Homogenity Electromagnetic induction Self induction None of these 31 / 35 The magnetic flux linked with a coil is changed from 1Wb to 0.1Wb in 0.1s. The induced emf is 4H 9V Both None of these 32 / 35 The current passing through a choke coil is 5H age decreasing at the rate of 3A/s . The emf induced in coil is 1.67 V -15V Both None of these 33 / 35 Lenz's law is associated with Charge Mass Energy Principle of conservation of momentum 34 / 35 Factors that affect the voltage generation in faraday's experiment is Number of coils Changing magnetic field Changing environment Option A and B 35 / 35 The law related with electromagnetic induction is called Newton's law Faraday's law Ohm's law Ampere's law Your score isThe average score is 51% 0% Restart quiz 1 12th Physics Chapter 7 MCQ Test तैयारी में दम है तो 36 में से 34 सही करके दिखाओं। 1 / 36 For resonance condition in any L-C-R circuit, the phase difference between applied voltage and current is π π/2 5 Zero 2 / 36 In step up transformer, the value of current and secondary coil compared to primary coil is Equal Less More None of these 3 / 36 The phase difference between current and voltage in only capacitive alternating current circuit is 0° 90° 180° None of these 4 / 36 Power factor is equal to R/Z R Z None of these 5 / 36 Inductive reactance for direct current is Zero Infinity Both None of these 6 / 36 Power factor for pure inductance is - 1 0 Infinity None of these 7 / 36 Power factor for wattless current is 0 Infinity Both None 8 / 36 If there are N1 and N2 turns in the primary and secondary coils respectively in a step down transformer, then N1>N2 N2>N1 N1=N2 None of these 9 / 36 Efficiency of transformer is the ratio of - Output voltage to input voltage Number of turns in secondary to number of turns in primary Output power to input current Output power to input power 10 / 36 The core of a transformer is laminated to stop Eddy currents Mass loss Magnetization None of these 11 / 36 The face difference between the current passing through an inductor and voltage across the inductor is an a.c circuit is 0 π/2 2 None of these 12 / 36 For which of the following, capacitor works as infinite resistance? DC AC Both None of these 13 / 36 L-C circuit is called- Oscillatory circuit Drift circuit Both None 14 / 36 Which of the following is correct for transformer ? It converts A.C into D.C It converts D.C into A.C It increases or decreases D.C voltage It increases or decreases A.C voltage 15 / 36 The power factor of series LCR circuit is R Z/R R/Z RZ 16 / 36 The power factor of a series LCR circuit is R Z/R R/Z RZ 17 / 36 A choke coil has High inductance and high resistance High inductance and low resistance Low inductance and low resistance None of these 18 / 36 A choke coil is used to control A.C D.C Both A.C and D.C None of these 19 / 36 Alternating current of 3A is the same as 3 coulomb/ metre 3 ohm / metre 3 joule / coulomb None of these 20 / 36 An A.C circuit containing only resistance , Voltage and current have the same frequency Voltage and current have same phase difference Voltage and current have same phase difference π None of these 21 / 36 An A.C circuit containing only resistance, which is not correct. The resistor causes to unknown reversible conversion of electrical energy to thermal energy Voltage and current have the same frequency Voltage and current are in phase Voltage and current have pd.π/2 22 / 36 Alternating current can be produced by A transformer An electric motor Heating effect A dynamo 23 / 36 Alternating current shows Chemical effect Magnetic effect Heating effect All the above 24 / 36 The frequency of A.C in India is 25 HZ 50 HZ 30 HZ 60HZ 25 / 36 The power factor is for Pure resistor only Pure indicator only Pure capacitor only None of these 26 / 36 Reactance of the capacitor with the frequency of alternating current. Decreases Increases Either decreases or increases None of these 27 / 36 The thermal effect of alternating current is practically Joule heating Peltier heating Thomson effect None of these 28 / 36 For long distance power transmission by using a transformer, the transformer at the source should be Step up Step down Any of A and B None of these 29 / 36 Induction furnace is based on the principle of Eddy current Self induction Mutual induction None of these 30 / 36 S.I unit of impedance is - Henry Ohm Tesla None 31 / 36 Transformer works utilise Self induction Mutual induction Heating None of these 32 / 36 A transformer works on D.C only A.C only Both None 33 / 36 Which of the following material is most suitable to be used for making the core of a transformer. Soft iron Copper Stainless steel Alnico 34 / 36 In LCR circuit energy laws in circuit is - In inductance In resistance In condenser None of theseNone of these 35 / 36 The core of transformer is laminated to prevent - Energy loss Mass loss Charge loss None of these 36 / 36 By use of a capacitor in induction coil, the emf in secondary is Increased Decreased Not changed Reduced to zero Your score isThe average score is 33% 0% Restart quiz 0 12th Physics Chapter 8 MCQ Test तैयारी में दम है तो 35 में से 33 सही करके दिखाओं। 1 / 35 The phase difference between electric wave and magnetic wave in the electromagnetic wave is 2 π/2 9 Zero 2 / 35 Clouds reflect - Micro waves Radio waves Infrared rays Ultraviolet waves 3 / 35 Which of the following waves has a maximum frequency ? Infrared waves Gamma rays Microwaves Radio waves 4 / 35 According to the law of electromagnetism, the speed of electromagnetism in all the inertial frames is - Same Different Not definite None of these 5 / 35 The average intensity I, mean energy density u and speed c of an electromagnetic wave in free space are related together as I=cu Ic=u Iu=c None of these 6 / 35 According to Maxwell's hypothesis, changing electric field gives rise to? Introduced EMF Electric field Magnetic field None 7 / 35 Which of the following help us for recognization of precious stone? Ultraviolet rays Infrared X-rays None 8 / 35 Which is a wrong statement ? Electromagnetic waves are transverse. Electromagnetic waves travel in a vacuum at a speed of light The speed of electromagnetic wave is the same in all media Electromagnetic waves are emitted by accelerated charges 9 / 35 Maxwell equations represent four laws of electromagnetism. Maxwell amphere law relates To total current To displacement current To conduction current None of these 10 / 35 Which type of e.m. wave is used for purification of water? Infrared rays Ultraviolet rays Radio wave All of above 11 / 35 Infrared rays are between the regions - Radio waves and microwaves Microwaves and visible light Visible light and ultraviolet regions None of these 12 / 35 Main effect of infrared waves is Sensation of vision Thermal effect Photoelectric effect None of these 13 / 35 Which is correct for velocity of light ? E/B B √E E.B 14 / 35 The energy of an electromagnetic field is due to its Wavelength Frequency Electric and magnetic fields None of these 15 / 35 Which one of the following is used to investigate the structure of solids? Gamma rays Infrared rays X rays Cosmic rays 16 / 35 A Displacement current is produced Only by a varrying magnetic field Only by a varrying electric field By varrying electric and by a varying magnetic field None of these 17 / 35 X-rays are Moving electron Moving positive ion Moving negative ion Electromagnetic waves 18 / 35 Which of the following is not electromagnetic wave ? Light waves X-rays Sound waves Infrared rays 19 / 35 Which rays are used for cooking and heating - Infrared Ultraviolet Microwave None of these 20 / 35 Which of the following are used to make labs free from bacteria? U-V rays I-R rays X-rays None 21 / 35 Electromagnetic waves can be - Light X-rays Infrared All the these 22 / 35 The energy of an electromagnetic radiation is 13.2keV. This radiation is related to which region of spectrum? Visible X-rays Ultraviolet Infrared 23 / 35 What is the phase difference between electric and magnetic fields in an electromagnetic wave ? 0 1 2 π 24 / 35 Which of the following is not shown by electromagnetic wave? Reflection Polarization Diffraction None of these 25 / 35 Nature of electromagnetic wave is - Longitudinal Transverse Neither longitudinal not transverse Both transverse and longitudinal 26 / 35 Which of the following prove that electromagnetic waves are transverse? Reflection Diffraction Interference Polarization 27 / 35 Which type of e.m. wave is used for treatment of muscular strain? Infrared rays Ultraviolet rays Radio waves Microwaves 28 / 35 In an electromagnetic wave, the disturbance is (are) E only B only Both E and B None of these 29 / 35 The electric field E , magnetic field B and speed of wave c are related together as B= cE C=BE E=Bc None of these 30 / 35 Electromagnetic wave in free space is Longitudinal Transverse Progressive None of these 31 / 35 The phase difference between electric and magnetic fields in an electromagnetic wave is- 0 π/2 π Anything 32 / 35 Nature of electromagnetic waves is - Transverse Longitudinal Both None of these 33 / 35 X-rays are capable of penetrating Bones Metallic materials Human flesh All of above 34 / 35 Water molecule in foods have a rotational frequency in the range of Ultraviolet waves Infrared waves Microwaves Visible waves 35 / 35 The ratio of the Speeds of microwaves and X-rays in vacuum is 1:2 1:4 1:1 None of these Your score isThe average score is 0% 0% Restart quiz 1 12th Physics Chapter 9 MCQ Test तैयारी में दम है तो 35 में से 33 सही करके दिखाओं। 1 / 35 The dispersive power of a prism depends upon - Refracting angle of prism Nature of material of prism Breadth of base of prism Angle of incidence 2 / 35 To overcome astigmatism lens used is - Concave lens Convex lens Cylindrical None of these 3 / 35 Minimum distance between real image formed by convex lens and object is- Four times Two times Three times of focal length None of these 4 / 35 The power of convex lens of focal length 20 cm in dioptre is 4 5 3 2 5 / 35 A convex lens is dipped in a liquid, whose refractive index is equal to refractive index of material of lens, then it's focal length will - Becomes zero Become infinite Decreases Increases 6 / 35 The focal length of plane mirror is- Unity Infinity Zero None of these 7 / 35 When concave lens of glass is immersed in water , it becomes Less convergent Convergent Less divergent More divergent 8 / 35 The radius curvature of plane mirror is Zero 5 Infinite None of these 9 / 35 For which of the following pairs is the critical angle the smallest? Water-air Glass-water Glass-air Glass-glass 10 / 35 In plane mirror, the image is - Always virtual Always real Both A and B are correct None of these 11 / 35 SI unit of power of lens is - Joule Candela Dioptre Watt 12 / 35 The radius of curvature of a spherical mirror is 40cm . It's focal length will be 30cm 20cm 10cm None of these 13 / 35 Or increasing the length of the tube of compound microscope, magnifying power Increases Decreases Does not change Becomes zero 14 / 35 Cylindrical lens is used to correct - Myopia Hypermetropia Presbyopia Astigmatism 15 / 35 The magnifying power of a magnifying glass of power 12 dioptre is 4 1200 3 25 16 / 35 The lens which is used to remove short sightedness is Concave Convex Cylindrical Plano-convex 17 / 35 Rainbow is a natural example of Refraction Reflection Refraction reflection and dispersion None of these 18 / 35 Which has larger difference in focal length between eye lens and objective lens ? In telescope Compound microscope In both None of these 19 / 35 To remove hypermetropia (long sightedness) lens used is- Convex Concave Cylindrical Plano-convex 20 / 35 When there is a refraction of light then which of the following does not change? Wavelength Frequency Speed Amplitude 21 / 35 When a Ray of light enters a glass slab its wavelength Decreases Increases Remains unchanged Data are not complete 22 / 35 The image formed by objective lens of a compound microscope is- Virtual and diminished Real and diminished Real and large Virtual and large 23 / 35 When length of compound microscope increases its magnifying power- Decreases Increases Becomes zero None of these 24 / 35 Which of the following phenomena taken place when a monochromatic light is incident on a prism? Dispersion Deviation Interference All of the above 25 / 35 Cause of mirage is Refraction and total internal reflection Diffraction Scattering Interference 26 / 35 Magnification is the ratio of - Image height to object height Image distance to object distance from focus Focal length to image distance None of these 27 / 35 The optical fibre works on the principle of Scattering Refraction Dispersion Total internal reflection 28 / 35 Lesser beam is Highly monochromatic Depends on the energy Without direction wave None of these 29 / 35 The final image in astronomical telescope is Real and erect Real and inverted Virtual and inverted Virtual and erect 30 / 35 Optical fibre communication is based on which of the following phenomena- Total internal reflection Scattering Reflection Interference 31 / 35 When the tube length of microscope is increased, it's magnifying power Increases Decreases Becomes zero Remains unchanged 32 / 35 The refractive index of diamond is about 1 2 2.42 3 33 / 35 The power of a convex lens of focal length 10 cm will be -10D +10D 95D +5D 34 / 35 An air bubble inside water works as- Diverging lens Diverging mirror Convex lens None of these 35 / 35 When any convex lens is drown into water then its power Increases Decreases Equals Infinity Your score isThe average score is 25% 0% Restart quiz 0 12th Physics Chapter 10 MCQ Test तैयारी में दम है तो 35 में से 33 सही करके दिखाओं। 1 / 35 When two light waves interfere there at some points there is brightness and at some point there is darkness where energy goes at those point Convert into heat There is redistribution of light energy Transformation of heat energy into electrical energy None of these 2 / 35 The phase difference of the waves for constructive interference of light is Odd multiple of π Even multiple of π Integer multiple of π None of these 3 / 35 Interference of light is the redistribution of which of the following physical quantities ? Frequency Intensity Wavelength Speed 4 / 35 Which of the following factors does the intensity of light depend on? Frequency Wavelength Amplitude Velocity 5 / 35 The reason for the phenomenon of interference is Phase difference Change in amplitude Velocity change Intensity change 6 / 35 Which of the following confirms transverse wave nature of light ? Interference Reflection Polarisation Dispersion 7 / 35 What is the geometric shape of the wavefron that originates when a plane wave passes through a convex lens? Converging spherical Diverging spherical Plane None of the above 8 / 35 The wavefront due to a point source at a finite distance from the source is Spherical Cylindrical Plane Circular 9 / 35 The wave theory failed to explain Interference Diffraction Polarisation All of these 10 / 35 In the interference of waves Energy is dissipated in totality Energy is created in totality Energy is neither lost nor created there is only a redistribution of energy Nothing can be said 11 / 35 Light waves coming from two electric bulb do not interfere because they are Coherent Not coherent Not equal None of these 12 / 35 The wave from due to a point source at an infinite distance from the source is Spherical Cylindrical Plane Circular 13 / 35 In interference there is redistribution of Mechanical energy Light energy Heat energy None of these 14 / 35 The phase difference of the waves for destructive interference of light is Odd multiple of π Even multiple of π Integer multiple of π None of these 15 / 35 The wave front due to and unknown source at an infinite distance from the source is spherical Cylindrical Plane Circular 16 / 35 Which of the following light phenomena confirms the transverse nature of light? Refraction of light Diffraction of light Dispersion of light Polarization of light 17 / 35 The nature of light waves is Longitudinal Transverse Sometimes transverse and sometimes longitudinal None of these 18 / 35 What is the locus of all the particles in a medium vibrating in the same phase called? Fringe Wavelet Wavefront None of these 19 / 35 Polarization can be done of electric magnetic wave By lens By mirror By Polaroid By prism 20 / 35 In a young's double split experiment if red light is replaced by yellow light the Fringe width Increases Decreases Firstly increase then decrease None of these 21 / 35 Huygen's secondary wave principle is used to New geometrical position of Wevefront Explain the superposition principle of waves Explain the interference of light Explain the polarization of light 22 / 35 If in young's double slit experiment distance between split & screen is made half than width of fringe will - Remain same Become half Four times None of these 23 / 35 Polaroid glasses are used in sunglasses because They are cheaper They have a good colour They look fashionable They reduce the light intensity to half on account of polarization 24 / 35 If a thin transparent sheet is placed before young's double slit then width of fringe Increases Decreases Remains unchanged None 25 / 35 The wavefron due to a line source at finite distance from the source is Spherical Cylindrical Plane Circular 26 / 35 Huygen's assumed light wave to be Longitudinal Transverse Both None 27 / 35 The concept of secondary wavelets was given by Fresnel Maxwell Huygens Newton 28 / 35 Light is a transverse wave because it shows Reflection Polarization Interference Diffraction 29 / 35 Which of the following will not cause of polarisation? Reflection Double refraction Scattering Diffraction 30 / 35 Which is used to produce polarised light? Prism of flint glass NaCl prism Nicol prism Biprism 31 / 35 Who discovered poisson's bright spot? Fresnel Rayleigh Fraunhofer Poisson 32 / 35 The resolving power of human eye in minute is 1/60 1 10 4 33 / 35 The width of diffraction fringes is ______ to the width of interference fringes . Equal Unequal Similar None of these 34 / 35 Two light sources are set to be coherent when both the sources of light emit light of The same amplitude and phase The same intensity and wavelength The same speed The safe wave length and constant phase difference 35 / 35 When the distance between source of light and screen is increased the Fringe width Increases Decreases Remain same None of these Your score isThe average score is 0% 0% Restart quiz 0 12th Physics Chapter 11 MCQ Test तैयारी में दम है तो 35 में से 33 सही करके दिखाओं। 1 / 35 What does a cathode ray consist of? Electrons Protons Photons Alpha particles 2 / 35 The energy of a photon is 1MeV . Which part of electromagnetic spectrum will it belong to ? X-rays Y-rays Microwave None of these 3 / 35 Photon does not possess Energy Momentum Rest mass Frequency 4 / 35 How does retarding potential vary with the frequency of light causing photoelectric effect ? Infinite Zero Decreases Increases 5 / 35 If the intensity of the radiation incident on a photosensitive plate is doubled, how does the stopping potential change? Increases Decreases No effect Infinite 6 / 35 For same wavelength of electron and proton which physical quantity will be same ? Velocity Energy Momentum Angular momentum 7 / 35 Electron volt is a unit of Charge Potential difference Current Energy 8 / 35 An electron is accelerated by potential drop of V. The De Broglie wavelength will be Ev Itv Mev None of these 9 / 35 An electron and a photon each have a wavelength of 1.00nm. which has greater momentum? Electron Photon Both have equal value of momentum None of these 10 / 35 Photos are deflected by Magnetic field only Electric field only Electro magnetic field None of the above 11 / 35 Who gave the theory of quantization of electric charge? JJ Thomson William crooks RA millikan William 12 / 35 De Broglie relation is true for all Charge particles Uncharged particles Particles whether charged or uncharged None of these 13 / 35 Work function is the energy needed to Excite an atom Produce X-rays Expel an electron just outside the surface of material To explore an atom 14 / 35 If the intensity of incident radiation in a photo cell is increased how does the stopping potential vary? Increases Remains same Decreases Infinite 15 / 35 Cathode rays behave like - Proton Electron Photon Neutron 16 / 35 In photoelectric effect, the photoelectric current is independent of Intensity of incident light Potential difference applied between two electrodes The nature of emitter material Frequency of incident light 17 / 35 The nature that was established by Davisson-Germer experiment, was Partical nature Wave nature Charge particles None of these 18 / 35 Which one of the following deflected in electric field? Gamma rays X-rays Ultraviolet rays Cathode rays 19 / 35 The maximum kinetic energy of photoelectrons emitted ine photoelectric effect depends linearly upon Square of frequency of incident light Frequency of incident light Wavelength of incident light Square of wavelength of incident light 20 / 35 A photoelectric cell is a device which Converts light energy into electricity Convert electricity into light energy Stores light energy Stores electricity 21 / 35 To beams one of red light and other of blue light of the same intensity are incident on a metallic surface to emit photo electrons which emits electron of greater frequency? red light Blue light Both None 22 / 35 The photoelectric effect is based on the law of conservation of Energy Momentum Mass Angular momentum 23 / 35 What happens to the kinetic energy of the emitted electrons when the light is incident on a metal surface ? It veries with the frequency of light It veries with the light intensity It veries with the speed of light It veries irregularly 24 / 35 Work function of copper is the order of Electron volt Joule Watt Volt 25 / 35 When light enters from one medium into another medium, which quantity does not change ? Wavelength Frequency Speed Amplitude 26 / 35 Work function of copper is- 4.65 2.75 4.17 None 27 / 35 Which of the following Photon is of greater energy? Visible Infrared Ultraviolet None of these 28 / 35 Matter waves are associated with material particles only if they Are in motion Are not in motion Have infinite speed None of these 29 / 35 And energy associated with a photon is 10keV. It belongs to X-rays Y-rays Ultraviolet rays Microwaves 30 / 35 Work function of silver is 4.70eV 4.60eV G Ev 31 / 35 The momentum of a particle is doubled. By what factor is wavelength changed ? 1/2 2 3 4 32 / 35 Energy of photon is equal to hv H Hb V 33 / 35 Which of the following does the wave theory of light not explain? Diffraction Photocurrent Polarization Interference 34 / 35 The emission of electrons does not occur in which of the following? Photoelectric emission Thermionic emission Secondary emission X-ray emission 35 / 35 The phenomena in which electrons are emitted from some metal surfaces when light falls on them is known as Photoelectric effect Photography Photometry Photosynthesis Your score isThe average score is 0% 0% Restart quiz 0 12th Physics Chapter 12 MCQ Test तैयारी में दम है तो 36 में से 34 सही करके दिखाओं। 1 / 36 What did ratherford Alpha particle experiment prove? Electron Protons Neutrons Nucleus 2 / 36 Who discovered the first spectral series? Lyman Balmer Paschen Pfund 3 / 36 All energy States above the ground state are called Stationery state Excited state Both None 4 / 36 The work done that must be done to remove an electron from an atom is called Excitation energy Ionisation energy Both None 5 / 36 The Kinetic energy of the Alpha particle incident on the gold foil is doubled. The distance of closest approach will also be doubled True False 6 / 36 Hydrogen atoms are excited from ground state to the state of principal quantum number 4. Then what will be the number of spectral lines observed? 3 6 5 2 7 / 36 The difference between the energy of an excited state and the energy of ground state is called the Ionization energy Excitation energy Both None 8 / 36 Electrons in the atoms are held to the nucleus by Nuclear force Coulomb's force Gravitational force None of these 9 / 36 Which of Bohr's result for H-atom is experimently wrong? Ground state energy is 13.6eV Ionization potential is 13.6V Explain energy spectrum Ground state angular momentum is h/2π 10 / 36 Which of the following series of the hydrogen spectrum lies wholly in ultraviolet region? Lyman series Balmer series Paschen series None of these 11 / 36 The significant result deduced from Rutherford's scattering experiment is that The whole of the positive charge is concentrated at the centre of an atom There are neutron inside the nucleus Alpha particles are hydrogen nuclei Electrons are embedded in the atom 12 / 36 The Rutherford's scattering experiment discovered the existence of Negatively charged nucleus Positively charged nucleus Neutrons in nucleus Equipartition of positive charge in atom 13 / 36 Which one is not divisible? Atom Nucleus Photon None of these 14 / 36 According to the Rutherford's model of atom was Stable Unstable Semi stable None of these 15 / 36 According to Bohr's curi when electron jumps down from an orbit of higher energy to the third orbit, the spectral lines so emitted are called Balmer series Paschen series Lyman series Pfund series 16 / 36 The hydrogen uncertainty principle is - Contained in Bohr's model Against Bohr's model Obtained from Bohr's model None of these 17 / 36 Which of the following series of hydrogen spectrum is in visible range? Lyman series Balmer series Paschen series Brackett series 18 / 36 The bohr model of atoms uses Einstein's photoelectric equation. True False 19 / 36 According to the classical theory, the circular path of the electrons is Circular Parabolic Spiral Straight line 20 / 36 Why was Rutherford's atomic model unstable? Electrons do not remain in orbit Nuclei will breakdown The nucleus repels electrons Orbiting electrons radiate energy 21 / 36 What is the valence electron in alkali metal? F electron P electron S electron D electron 22 / 36 Which of the following is not charged? Photon Alpha particle Beta particle Electron 23 / 36 The helium atom does not contain - Two protons Two neutrons Two electrons Six nucleons 24 / 36 Which of the following did bohr use to explain his theory ? Quantization of angular momentum Conservation of an Quantum frequency Conservation of mass Conservation of linear momentum 25 / 36 Electrons in the atoms are held due to Nuclear forces Gravitational forces Coulomb's forces None of these 26 / 36 If an Alpha particle collides head on with a nucleus, what is its impact parameter ? Zero Infinite 1 17 27 / 36 The experiment that supported Bohr's idea that there are discrete energy levels in atoms and the process of photon emission, was Frank-Hertz experiment Rutherford scattering experiment Davisson-German experiment None of these 28 / 36 The electrons of Rutherford's model would be expected to lose energy because They jump on the nucleus They move randomly Radiate electromagnetic waves Escape from the atom 29 / 36 Which series of hydrogen spectrum does not lie in infrared region? Humphreys series Pfund series Brackett series Lyman series 30 / 36 The binding energy of the hydrogen atom is Infinite Zero 1 -13.6eV 31 / 36 The Rutherford's experiment confirm that Coulomb's law holds for atomic dimensions Coulomb's law does not hold for atomic dimensions Ampere circuital law hold for atomic dimensions None of these 32 / 36 Which source is associated with a line emission spectrum? Electric fire Neon street sign Red traffic light Sun 33 / 36 The minimum orbital angular momentum of an electron in a hydrogen atom is h h/2 h/2π H 34 / 36 What is the ratio of minimum to maximum wavelength in the balmer series ? 5:9 5:36 1:4 3:4 35 / 36 According to the uncertainty principle of an electron time measurement will become uncertain if which of the following is measured with high certainty? Energy Momentum Location Velocity 36 / 36 According to the Rutherford's model of atom was Stable Unstable Semi stable None of these Your score isThe average score is 0% 0% Restart quiz 0 12th Physics Chapter 13 MCQ Test तैयारी में दम है तो 36 में से 34 सही करके दिखाओं। 1 / 36 Which of the following is not a fundamental particle? Neutron Proton Alpha particle Electron 2 / 36 The number of neutrons in nucleus is - A+Z A-Z Z+A/2 Z 3 / 36 Beta rays are deflected in Gravitational field Only in a magnetic field Only in electric field Both in magnetic and electric fields 4 / 36 The source of solar energy is Nuclear fission Chemical reaction Annihilation of elementary particles Nuclear fusion 5 / 36 The unit of radioactivity is Me Curie AMU Joule 6 / 36 Beta rays are fast moving Photons Protons Electrons Neutron 7 / 36 Which of the following is correct for Alpha particle? Electron Electromagnetic radiation Helium nucleus Hydrogen nucleus 8 / 36 The time in which radioactive substance became half of its initial amount is called Average life Half Life Time period Decay constant 9 / 36 The radius of a nucleus is Directly proportional to its mass number Inversely proportional to its atomic weight Directly proportional to the cube root of its mass number None of these 10 / 36 What is the unit of radioactivity? Joule Mev amu Curie 11 / 36 Which of the following mass number related to Alpha activity ? 1 100 180 212 12 / 36 The usual constituents of a nucleus are Protons Protons and neutrons Alpha particles Protons and electrons 13 / 36 The half Life period of a radioactive isotope is 5 years. After 15 years the fraction decayed will be 1 1/8 7/8 5/8 14 / 36 The quantities, which remain conserved in a nuclear reaction - Total charge Angular momentum Linear momentum All of the above 15 / 36 The function of moderator in nuclear reactor is to Slow the speed of neutrons Fast the speed of neutrons Slow the speed of electrons Fast the speed of electrons 16 / 36 Two nuclei of isobars of an element must have Equal number of neutrons Equal number of protons Equal mass numbers Unico number of protons 17 / 36 In nuclear reactors, the control rods are made of Cadmium Graphite Krypton Plutonium 18 / 36 To isotopes of an element have equal number of- Equal number of neutrons Equal number of protons Equal number of protons and neutrons None of these 19 / 36 The values of N/Z for stable nuclei are : 1-1.6 1.6-2.0 3.0-4.0 4.0 20 / 36 The constituents of nucleus are Electrons and protons Protons and neutrons Neutrons and electrons Electrons protons and neutrons 21 / 36 X rays was discovered by Becqueral Marie Curie Roengton Vanlaw 22 / 36 Which one of the following has maximum penetrating power ? X-rays Cathode rays Alpha rays Gamma rays 23 / 36 Which particle must be emitted with beta particle from nucleus? Proton Neutrino Neutron None of these 24 / 36 The nucleus of any atom is made up of Proton Proton and electron Alpha particle Proton and neutron 25 / 36 The half life of radioactive nucleus is 20h. What fraction of original its activity Be just after 40h? 1/4 1/8 1/2 1/16 26 / 36 Atomic number decreases with the emission of Alpha particles from the nucleus by 1 2 3 4 27 / 36 Life of a fossil in estimated by Carbon dating X-rays Laser Y-rays 28 / 36 X-rays are emitted in Beta Alpha Electron capture None of these 29 / 36 Gamma rays are similar to Alpha rays Beta rays Cathode rays X-rays 30 / 36 Which of the relations is correct for radioactive atom? Half life = average life Half life = 2× average life Half life = 1.6931× average life Half life = 0.6931× average life 31 / 36 Mass defect per nucleon is called Packing fraction Energy defect Momentum defect None of these 32 / 36 The specific binding energy of nucleus is ____then binding energy . Greater Smaller Lowest None of these 33 / 36 The mean life of a radioactive substance is 100 years. It's half life will be 50 years 100/2 ×0.06 years 69.3 years None of these 34 / 36 The reason for high penetrating power of Gamma rays is Short wavelength Long wavelength Absence of charge Both a and c 35 / 36 First nuclear reaction has been done by Chadwick Einstein Pauli Rutherford 36 / 36 Two nuclei of isobars of an element must have Equal number of neutrons Equal number of protons Equal mass numbers Unico number of protons Your score isThe average score is 0% 0% Restart quiz 0 12th Physics Chapter 14 MCQ Test तैयारी में दम है तो 36 में से 34 सही करके दिखाओं। 1 / 35 In full wave rectification if input frequency is 50 Hz then output frequency will be- 50HZ 100HZ 2HZ 20HZ 2 / 35 The temperature coefficient of a semiconductor is Positive Negative Zero Infinity 3 / 35 A semi conductor is cooled from T1K to T2K , then its resistance will- Increase Decrease Remains constant First decrease then increase 4 / 35 The minority current carry in p type semiconductor are Electrons Holes Photon Protons 5 / 35 Full wave rectifier uses Two diodes Three diodes Four diodes Five diodes 6 / 35 In binary system 111 represent 1 7 3 100 7 / 35 Which one of the following logic gates is universal logic gate ? OR AND NOT NAND 8 / 35 With the increase of temperature, the resistance of a semiconductor Increases Decreases Sometimes increases and sometimes decreases Remains unchanged 9 / 35 Junction transistor with back to back on junction was discovered by J.Barden W.H brattain Both W schockely 10 / 35 Width of forbidden band is maximum for Metals Semiconductors Insulators None of these 11 / 35 Main gate (basic gate) is- AND ,OR OR ,NOT NAND , OR AND , OR , NOT 12 / 35 A P-type semiconductor is Positively charge Negatively charge Uncharged Absolute zero 13 / 35 For P-N-P transistor with common base , the value of Alpha is 0.98 , then common emitter current hain beta will be 5 2 89 49 14 / 35 Transistor can act as a switch in Saturation mode Cut off mode Both None 15 / 35 The Boolean expression for AND gate is A+B A Y=A.B None 16 / 35 The device to convert solar energy into electrical energy is Solar cell Dry cell Accumulator Botton cell 17 / 35 Diode maybe used to Change AC into DC Change DC into AC As an amplifier None 18 / 35 Which of the following is the Boolean expression of OR gates A+B=Y A.B=Y A+B A-B 19 / 35 Majority carries in p type semiconductors are Electrons Holes Photons Protons 20 / 35 The impurity to get p type germanium or silicon semi conductor should be Trivalent Tetravalent Pentavalent None 21 / 35 To obtain an oscillator from an amplifier the type of feedback used is Positive Negative Sometimes positive and sometimes negative None 22 / 35 Which configuration of transistor has highest voltage gain ? Common base Common emitter Common collector None 23 / 35 In a transistor ,the majority charge carries are communicated towards the base by the part Emitter Base Collector None 24 / 35 For obtaining p type semiconductor travelent material is mixed in germanium but for obtaining and type semiconductor which is fixed with ge- Tetravalent Pentavalent Trivalent None 25 / 35 For semiconductors the gap between valence and conduction energy bands is Wide band gap Narrow band gap Band gap that is neither norwide None of these 26 / 35 In N type semiconductors , majority charge carriers are Protons Holes Alpha particles Electrons 27 / 35 At zero degree Kelvin the piece of germanium Is semiconductor Is good conductor Is bad conductor Keeps maximum conductivity 28 / 35 For NPN transistor is common base beta is 100 the current gain Alpha for common emitter will be 0.99 1.01 0.9 0.98 29 / 35 The impurity element used for p type semiconductor is Boron Bismuth Arsenic Phosphorus 30 / 35 The group third element used asants for germanium and silicon gives us Insulator N type semiconductor P type semiconductor None 31 / 35 Unit of amplification factor of transistor is Volt Ampere Ohm No unit 32 / 35 Diode is used as Amplifier Oscillator Modulator Rectifier 33 / 35 (1+1) in binary addition is 1 0 10 100 34 / 35 When LED is reserved biased, Light is not emitted Light is emitted Light is not even abserved None 35 / 35 The gap between conduction energy band and valence energy band is called Forbidden energy gap Band gap Valence band Conduction band Your score isThe average score is 0% 0% Restart quiz 1 12th Physics Chapter 15 MCQ Test तैयारी में दम है तो 34 में से 32 सही करके दिखाओं। 1 / 34 Which range of frequency is used in TV transmission? 30HZ-300HZ 30KHZ 30MHz-300MHz 0 2 / 34 Information in AM wave is contained in Carrier only Carrier wave Only in side bands Only in high side bands 3 / 34 Which frequency range is used for TV transmission? 2 70 30MHz-300MHz 30GZ-47Hz 4 / 34 The maximum electron density of the inosphere on a day is directly proportional to Critical frequency Square of critical frequency Both None 5 / 34 On a particular day the maximum frequency related from the ionosphere is 10 mhz on the other day it was found to decrease to 8 mhz . what is the ratio of the maximum density of ionosphere on the 2 days 4:5 16:25 2:1 None 6 / 34 Unit of information is Bit Hertz Watt None 7 / 34 On a particular day the maximum frequency reflected from the ionosphere is 10 mhz on other day it was found to increase to 11mhz .the ratio of maximum electron density of the ionosphere on the two days density of ionosphere on the two days is 1.21:1 12 6 None 8 / 34 The height of a tv transmission Tower at any place on the surface of the Earth is 245 m. the maximum distance up to which transmission of Tower will reach is 245 m 245 km 56 km 128 km 9 / 34 Laser action needs High temperature Semiconductor High pressure Number inversion 10 / 34 Radio wave are reflected by- Inosphere Stratosphere Tropodhy None 11 / 34 In pulse modulation- Height of pulse is affected Width of pulse is modulated Pulse position is modulated All of these 12 / 34 The device given intense monochromatic parallel and highly coherent light beam is Laser Radar TV Computer 13 / 34 Superimposing information single on carreir wave is called Transmission Modulation Demodulation Reception 14 / 34 Range of UHf is 300MHz to 3000MHz 9272636 Mhz917 300khz 15 / 34 Modulation is of 2 types 3 types 4 types 5 types 16 / 34 For long distance radio broadcast mainly used means is Ground wave Visible wave Ionospheric reflection None of this 17 / 34 GPS is acronym for Global positioning system Global positioning of satellite Gross product of sugar None 18 / 34 Sky wave communication is based upon- Reflection by ionosphere Absorption by ionosphere Transmission through Ionosphere None 19 / 34 The communication suited to frequency about 40 mhz is by Ionosphere Satellite Ground wave None of these 20 / 34 Radar system uses Microwave Radiowave Infrared None 21 / 34 The height of geostationary Satellite from the ground is 725525km 35930km 6244482km 2579996km 22 / 34 Analogue communication may be related to - Amplitude modulation Frequency modulation Phase modulation All of these 23 / 34 Digital single comprise of One bit words Fore bit words or their multiples Two bit word or their multiples None 24 / 34 Space wave propagation , used in TV has a frequency range of 40MHz or more 10MHz 1MHz None 25 / 34 In frequency modulation the single affects - Amplitude Frequency Both a and b None 26 / 34 Which of the following units is correct to measure attenuation? Decibel Ohm Amphere Volt 27 / 34 Which is not an example of digital communication? Email Cellular phone Television network Satellite communication 28 / 34 Waves of UHf frequency are generally transmitted as Ground waves Sky waves Surface waves Space waves 29 / 34 The values possible in digital single are 0&1 All the values All the values between zero and one None 30 / 34 Range of microwaves is 2MHz 4Mhz 30kz-400kz 30MHz-300MHz 31 / 34 Meaning of FAX is - Full access transmission Facsimile telegraphy Factual auto access Feed auto exchange 32 / 34 What is the meaning of BER Bit efficiency ratio Bit error ratio Brand efficiency ratio Bit error rate 33 / 34 In amplitude modulation- Amplitude is kept constant Frequency is according to modulated voltage Amplitude changes according to modulating voltage Amplitude changes according to modulating frequency 34 / 34 WWW is acronym for World wide wire World wide web World wide wise None Your score isThe average score is 44% 0% Restart quiz
