HBSE Class 12 Physics MCQ Important Question Answer 2024

Class 12 Physics Important Question Answer solution with pdf. Here We Provides Class 1 to 12 all Subjects NCERT Solution with Notes, Question Answer, CBSE and HBSE Important Questions, MCQ and old Question Papers for Students.

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HBSE ( Haryana Board ) Solution of Class 12 Physics important MCQ Question And Answer solution for 2024 exams.

HBSE Class 12 Physics Important MCQ Question Answer 2024

Chapter 1 Electric Charges and Fields

1. SI unit of electric charge is :
(A) Ampere
(B) Coulomb
(C) Volt
(D) None

Answer

Ans – (B) Coulomb

2. SI unit of k (proportionality constant in coulomb’s law) is :
(A) N¹C^-2m²
(B) N¹C²m^-2
(C) N¹C²m^-2
(D) N^–¹C^-2m²

Answer

Ans – (A) N¹C^-2m²

3. Nature of electric force between two protons is :
(A) Attractive
(B) Neutral
(C) Repulsive
(D) None of the above

Answer

Ans – (C) Repulsive

4. SI unit of ε₀ (permittivity of free space) is :
(A) C^-2N¹m^-2
(B) C²N^-1m^-2
(C) N¹C²m^-2
(D) N^-1C²m²

Answer

Ans – (B) C²N^-1m^-2

5. Two charges +1μc and + 8μc are situated at a distance in air. The ratio of forces acting on them is :
(A) 1:8
(B) 8:1
(C) 1:1
(D) 1:16

Answer

Ans – (C) 1:1

6. When the distance between two charged particles is made one- fourth, the force between them becomes :
(A) one-fourth
(B) one-third
(C) half
(D) sixteen times.

Answer

Ans – (D) sixteen times.

7. When the distance between two charged particles is made one- third, the force between them becomes :
(A) one-third
(B) half
(C) one-fourth
(D) nine times

Answer

Ans -(D) nine times

8. When the distance between two charged particles is halved, the force between them becomes :
(A) one-fourth
(B) half
(C) double
(D) four times

Answer

Ans – (C) double

9. Ratio of magnitudes of electric force in air and water between an electron and proton is:
(A) K (dielectric constant )
(B) $\displaystyle \frac{1}{K}$
(C) 1
(D) 0

Answer

Ans -(C) 1

Chapter 2 Electrostatic Potential and Capacitance

1. How much current is flowing through a 3 kΩ resistor when a potential difference of 6V is applied across its ends?
(A) 2 μA
(B) 2 mA
(C) 2 A
(D) 6 A

Answer

Ans -(B) 2 mA

2. The electric potential energy of a system of two positive point charges of 1 μc each placed in air 1 metre a part is:
(A) 1 Joule
(B) 1 electron-volt
(C) 9 x 10^-3 Joule
(D) Zero

Answer

Ans – (D) Zero

3. Three capacitors of equal capacity C are joined first in parallel and then in series. The ratio of equivalent capacities in both the cases will be:
(A) 9:1
(B) 6:1
(C) 3: 1
(D) 1:9

Answer

Ans -(B) 6:1

4. SI unit of electrostatic potential is :
(A) Ohm
(B) Coulomb
(C) Volt
(D) Ampere

Answer

Ans -(C) Volt

5. SI unit of capacitance is :
(A) Volt
(B) Ampere
(C) Coulomb
(D) Farad

Answer

Ans -(D) Farad

6. On introducing a dielectric material between two positive charges situated in air, the repulsive force between them will be:
(A) increased
(B) decreased
(C) the same
(D) zero

Answer

Ans – (B) decreased

Chapter 3 Current Electricity

1. The relation between electric current (I) and drift velocity (V_d) is :
(A) I= neV_d
(B) I = neAV_d

(D) $\displaystyle {{V}_{d}}=\frac{{neA}}{I}$

Answer

Ans -(B) I = neAV_d

2. The relation between current density (j) and electric current ( I ) is :
(A) j= V_dlA
(B) $\displaystyle j=\frac{A}{I}$
(C) $\displaystyle j=\frac{I}{A}$
(D) j = IA

Answer

Ans -(C) $\displaystyle j=\frac{I}{A}$

3. SI unit of electric current is:
(A) Volt
(B) Coulomb
(C) Ampere
(D) Farad

Answer

Ans -(C) Ampere

4. The relation between current density (j) and drift velocity (V_d) is :
(A) j = neV_d
(B) j = ne / V_d
(C) j = V_d / ne
(D) j = 1 / neV_d

Answer

Ans -(A) j = neV_d

5. “Ohm-metre” is unit of:
(A) Resistance
(B) Current density
(C) Resistivity
(D) Conductivity

Answer

Ans -(C) Resistivity

6. How much current is flowing through a 5 kΩ resistor when a potential difference of 5V is applied across its ends?
(A) 1 μA
(B) 1 mA
(C) 1 A
(D) 5 A

Answer

Ans -(B) 1 mA

7. How much current is flowing through a 20Ω resistor when a potential difference of 2V is applied across its ends ?
(A) 20 A
(B) 2 A
(C) 0.1 A
(D) 1.0 A

Answer

Ans -(D) 1.0 A

8. How much current is flowing through a 1 kΩ resistor when a potential difference of 2V is applied across its end?
(A) 2 μA
(B) 2 mA
(C) 2 A
(D) 1 A

Answer

Ans -(B) 2 mA

9. The length of a metallic wire of R ohm resistance is stretched two times its initial length. Its new resistance is :
(A) 2R
(B) 4R
(C) 6R
(D) 8R

Answer

Ans -(D) 8R

10. The length of a metallic wire of R ohm resistance is stretched four times its initial length. Its new resistance is:
(A) 8R
(B) 4R
(C) 12R
(D) 16R

Answer

Ans -(D) 16R

11. The unit of Specific resistance is :
(A) ohm-m
(B) ohm-m^-1
(C) ohm^-1-m^-1
(D) ohm^-1-m

Answer

Ans -(A) ohm-m

12. The length of a metallic wire of R ohm resistance is stretched n times its initial length. Its new resistance is :
(A) nR
(B) 2nR
(C) n²R
(D) n⁴R

Answer

Ans -(C) n²R

13. The best instrument for accurate measurement of emf of a cell is :
(A) Wheatstone bridge
(B) Ammeter
(C) A Potentiometer
(D) Voltmeter

Answer

Ans -(C) A Potentiometer

14. With the increase of temperature, the resistivity of a semiconductor:
(A) Decreases
(B) Increases
(C) May increase or decrease
(D) Does not change

Answer

Ans -(A) Decreases

15. With the increase in length of a conductor, its resistivity :
(A) Increases
(B) Decreases
(C) May increase or decrease
(D) Does not change

Answer

Ans -(D) Does not change

16. With the increase of temperature, the resistivity of a metal :
(A) Increases
(B) Decreases
(C) May increase or decrease
(D) Does not change

Answer

Ans -(A) Increases

17. The resistivity of a conductor with increase in temperature:
(A) increases
(B) decreases
(C) may increase or decrease
(D) does not change

Answer

Ans -(A) increases

18. With the increase of area of cross-section of a conductor, its resistivity :
(A) Increases
(B) Decreases
(C) May increase or decrease
(D) Does not change

Answer

Ans -(D) Does not change

19. With decrease in temperature, the resistivity of a conductor:
(A) increases
(B) decreases
(C) may increases or decreases
(D) does not change

Answer

Ans -(B) decreases

20. With increase in temperature the conductivity of a conductor:
(A) remains same
(B) decreases
(C) increases
(D) may increase or decrease

Answer

Ans -(C) increases

21. The conductivity of a semi-conductor with increase in temperature:
(A) decreases
(B) increases
(C) remains same
(D) may increase or decrease

Answer

Ans – (B) increases

22. With decrease in temperature, the mobility of a conductor:
(A) increases
(B) decreases
(C) may increase or decrease
(D) does not change

Answer

Ans -(A) increases

23. With increase in temperature, the mobility of electrons in a conductor :
(A) increases
(B) decreases
(C) may increase or decrease
(D) does not change

Answer

Ans -(B) decreases

24. The graph between voltage (v) and current (i) for a conductor is a straight line which makes an angle θ with x-axis (representing i). The resistance of the conductor will be:
(A) tan θ
(B) cot θ
(C) sin θ
(D) cos θ

Answer

Ans -(A) tan θ

25. The graph between voltage (v) and current (i) for a conductor is a straight line which makes an angle θ with y-axis (representing i). The resistance of the Conductor will be:
(A) tanθ
(B) cotθ
(C) sinθ
(D) cosθ

Answer

Ans -(B) cotθ

Chapter 4 Moving Charges and Magnetism

1. A moving charge produces :
(A) Electric field only
(B) Magnetic field only
(C) Both Electric and Magnetic fields
(D) None of the fields

Answer

Ans -(C) Both Electric and Magnetic fields

2. A proton enters into a uniform magnetic field perpendicularly to it. The path of the proton would be:
(A) Elliptical
(B) Circular
(C) Parabolic
(D) Linear

Answer

Ans – (B) Circular

3. An electron enters into a uniform magnetic field perpendicularly to it. The path of the electron would be:
(A) Elliptical
(B) Circular
(C) Parabolic
(D) Linear

Answer

Ans -(B) Circular

4. The force (F) acting on a particle of charge q moving with velocity (v) in magnetic field (B) is:
(A) $\displaystyle \frac{q}{{\overrightarrow{v}\times \overrightarrow{B}}}$
(B) $\displaystyle \frac{{\overrightarrow{v}\times \overrightarrow{B}}}{q}$
(C) $\displaystyle q(\overrightarrow{v}\times \overrightarrow{B})$
(D) $\displaystyle \overrightarrow{v}\times \overrightarrow{q}\times \overrightarrow{B}$

Answer

Ans -(C) $\displaystyle q(\overrightarrow{v}\times \overrightarrow{B})$

5. The force (F) acting on a particle of charge q moving with velocity ( $\displaystyle \overrightarrow{v}$ ) parallel to magnetic field ( $\displaystyle \overrightarrow{B}$ ) is :
(A) $\displaystyle \frac{q}{{\overrightarrow{v}\times \overrightarrow{B}}}$
(B) $\displaystyle \frac{{\overrightarrow{v}\times \overrightarrow{B}}}{q}$
(C) $\displaystyle q(\overrightarrow{v}\times \overrightarrow{B})$
(D) Zero

Answer

Ans -(C) $\displaystyle q(\overrightarrow{v}\times \overrightarrow{B})$

6. The magnetic field at distance r from a straight conductor of infinite length carrying current I, is given by : Most Important

(A) $\displaystyle \frac{{{{\mu }_{0}}I}}{{2\pi r}}$

(B) $\displaystyle \frac{{{{\mu }_{0}}I}}{{2r}}$
(C) μ₀nI
(D) Zero

Answer

Ans -(A) $\displaystyle \frac{{{{\mu }_{0}}I}}{{2\pi r}}$

7. The magnetic field at the centre of a circular coil of radius r and carrying current I, is given by: Most Important
(A) Zero
(B) μ₀nI
(C) $\displaystyle \frac{{{{\mu }_{0}}I}}{{2\pi r}}$

(D) $\displaystyle \frac{{{{\mu }_{0}}I}}{{2r}}$

Answer

Ans -(D) $\displaystyle \frac{{{{\mu }_{0}}I}}{{2r}}$

8. Two magnetic lines of forces :
(A) Cut each other at the neutral point
(B) Cut each other near north or south pole
(C) Never cut each other
(D) Cut at the middle of magnet

Answer

Ans – (C) Never cut each other

9. Moving coil galvanometer is converted into voltmeter by:
(A) Connecting high resistance in parallel
(B) Connecting low resistance in parallel
(C) Connecting high resistance in series
(D) Connecting low resistance in series

Answer

Ans -(C) Connecting high resistance in series

10. Moving coil galvanometer is converted into ammeter by:
(A) Connecting high resistance in parallel
(B) Connecting low resistance in parallel
(C) Connecting high resistance in series
(D) Connecting low resistance in series

Answer

Ans -(B) Connecting low resistance in parallel

11. The torque acting on an electric dipole of dipole moment P placed parallel to an electric field E will be:
(A) PE
(B) PE cosθ
(C) Zero
(D) None

Answer

Ans -(C) Zero

12. The torque acting on an electric dipole of dipole moment P placed at an angle 90° to the electric field E will be :
(A) PE
(B) PE cosθ
(C) PE / sinθ
(D) Zero

Answer

Ans -(D) Zero

13. Direction of Induced Current is given by :
(A) Lenz’s Law
(B) Fleming’s Left Hand Rule
(C) Biot-Savert’s Law
(D) Ampere’s Law

Answer

Ans -(A) Lenz’s Law

Chapter 5 Magnetism and Matter

1. The magnetic susceptibility of diamagnetic substance is :
(A) small and positive
(B) large and positive
(C) small and negative
(D) large and negative

Answer

Ans – (C) small and negative

2. Magnetic susceptibility of a paramagnetic substance is :
(A) small and positive
(B) small and negative
(C) large and positive
(D) large and negative

Answer

Ans – (A) small and positive

3. Magnetic susceptibility of a ferromagnetic substance is :
(A) large and negative
(B) large and positive
(C) small and negative
(D) small and positive

Answer

Ans – (B) large and positive

4. The tangent to the magnetic field line at a given point represents the direction of the net :
(A) Electric Force (F)
(B) Electric Field (E)
(C) Magnetic Field (B)
(D) Electric Current (I)

Answer

Ans – (C) Magnetic Field (B)

5. At a given place the horizontal and vertical components of earth are equal. The angle of dip at that place will be :
(A) 0°
(B) 45°
(C) 60°
(D) 90°

Answer

Ans -(B) 45°

6. The horizontal component of Earth’s magnetic field is zero at:
(A) Magnetic poles
(B) Geographic poles
(C) Every Place
(D) Magnetic equatorial

Answer

Ans -(A) Magnetic poles

7. The magnetic field lines of a magnet form:
(A) Continuous curve
(B) Continuous closed loops
(C) Like the electric dipole
(D) None of the above .

Answer

Ans – (B) Continuous closed loops

8. In the magnetic meridian at a certain location, the horizontal component of earth’s magnetic field is 0.16 G and angle of dip is 60°. The earth’s magnetic field at this location is :
(A) 0.32 G
(B) 0.36 G
(C) 0.18 G
(D) 0.16 G

Answer

Ans -(A) 0.32 G

9. In the magnetic meridian at a certain location, earth’s magnetic field is 0.52 G and the angle of dip is 60°. The horizontal component of earth’s magnetic field at this location is:
(A) 0.36 G
(B) 0.52 G
(C) 0.13 G
(D) 0.26 G

Answer

Ans -(D) 0.26 G

10. In the magnetic meridian of a certain place, earth’s magnetic field is 0.38 G and the angle of dip is 30°. The horizontal component of earth’s magnetic field at this location is:
(A) 0.19 G
(B) 0.38 G
(C) 0.33 G
(D) 0.57 G

Answer

Ans -(C) 0.33 G

11. In the magnetic meridian at a certain place, earth’s magnetic field is 0.32 G and its horizontal component is 0.16 G. The angle of dip of earth’s magnetic field at this location is :
(A) 30°
(B) 60°
(C) 45°
(D) 22°

Answer

Ans -(B) 60°

Chapter 6 Electromagnetic Induction

1. The magnetic flux threading a wire loop placed in a magnetic field depend upon :
(A) Area of the loop
(B) Magnitude of the field
(C) Orientation of the loop with respect to the field
(D) All of the above

Answer

Ans -(D) All of the above

2. The magnetic flux linked with a coil is decreased from 5 Weber to 2 Weber in 1 second. The induced electromotive force in the coil is :
(A) 3 Volt
(B) 30 Volt
(C) 300 Volt
(D) .3 Volt

Answer

Ans -(A) 3 Volt

3. The magnetic flux threading a wire loop placed in a magnetic field does not depend upon:
(A) Area of the loop
(B) Magnitude of the field
(C) Orientation of the loop with respect to the field
(D) Shape of the loop

Answer

Ans -(D) Shape of the loop

4. The magnetic flux linked with a coil is decreased from 1 Weber to .1 Weber in 1 second. The induced electromotive force in the coil is :
(A) 9 Volt
(B) 90 Volt
(C) .9 Volt
(D) .09 Volt .

Answer

Ans -(C) .9 Volt

5. Lenz’s law is a consequence of the law of conservation of :
(A) Charge
(B) Momentum
(C) Energy
(D) Mass

Answer

Ans -(C) Energy

6. On what factor does the coefficient of mutual inductance of two coils not depend?
(A) Filled with medium inside solenoid
(B) Separation between coils
(C) Their relative orientation
(D) Their resistances

Answer

Ans -(D) Their resistances

7. For a coil having self-inductance 3 mH current flows at a rate of 10³ ampere/sec. in it. The emf induced in it is :
(A) 1 Volt
(B) 2 Volt
(C) 3 Volt
(D) 4 Volt

Answer

Ans -(C) 3 Volt

8. For a coil-having self Inductance 2 mH, current 10³ ampere/sec in it. The emf induced in it is :
(A) 1 volt
(B) 2 volt
(C) 3 volt
(D) 4 volt

Answer

Ans -(B) 2 volt

Chapter 7 Alternating Current

1. An alternating current i = I₀ sin (ωt + π/2) is flowing in a circuit. The r.m.s. value of this current is:
(A) I₀
(B) I₀/ω
(C) I₀/√2
(D) ωI₀

Answer

Ans -(C) I₀/√2

2. An alternating current i= I₀ sin(ωt-π/2) is flowing in a circuit. The r.m.s. value of this current is:
(A) I₀
(B) I₀/ω
(C) I₀/√2
(D) ωI₀

Answer

Ans -(C) I₀/√2

3. An alternating current i = I₀sinωt is flowing in a circuit. The r.m.s. value of this current is:
(A) I₀/√2
(B) 2I₀
(C) I₀
(D) √2 I₀

Answer

Ans -(A) I₀/√2

4. The voltage across the ends of a resistor is v=V₀ sin wt. The r.m.s. value of this voltage is :
(A) V₀
(B) 2 V₀
(C) V₀/√2
(D) √2 V₀

Answer

Ans -(C) V₀/√2

5. An ac source is connected to a capacitor. The phase difference between applied voltage and the current flowing through it is :
(A) 0°
(B) 90°
(C) 180°
(D) 45°

Answer

Ans -(B) 90°

6. Phase difference between voltage and current when an ac source is connected to inductor is :
(A) 0°
(B) 90°
(C) 45°
(D) 180°

Answer

Ans -(B) 90°

7. An ac source is connected to a resistor. The phase difference between applied voltage and the current flowing through it is:
(A) 0°
(B) 45°
(C) 90°
(D) 180°

Answer

Ans -(A) 0°

8. The power factor for a purely capacitive circuit is :
(A) 1
(B) √2
(C) $\displaystyle \frac{1}{{\sqrt{2}}}$
(D) Zero

Answer

Ans -(D) Zero

9. The power factor for a purely inductive ac circuit is :
(A) 1
(B) Zero
(C) $\displaystyle \frac{1}{{\sqrt{2}}}$
(D) √2

Answer

Ans -(B) Zero

10. The path difference equivalent to π/4 phase difference is :
(A) λ
(B) λ/2
(C) λ/4
(D) λ/8

Answer

Ans -(C) λ/4

11. Two electric bulbs of 40 watt each are connected in series. The power consumed by the combination will be:
(A) 20 watt
(B) 60 watt
(C) 80 watt
(D) 100 watt

Answer

Ans -(C) 80 watt

Chapter 8 Electromagnetic Waves

1. In the electromagnetic wave, the phase difference between electric field and magnetic field is :
(A) 0
(Β) π/4
(C) π/2
(D) π

Answer

Ans -(A) 0

2. Microwaves are the electromagnetic waves with frequency in the range of:
(A) Micro hertz
(B) Mega hertz
(C) Giga hertz
(D) Hertz

Answer

Ans -(C) Giga hertz

3. Which of the following electromagnetic waves has smaller wavelengths?
(A) X-rays
(B) Microwaves
(C) γ-rays
(D) Radiowaves

Answer

Ans -(A) X-rays

4. Which of the following are electromagnetic waves ?
(A) Sound waves
(B) α-rays
(C) B-rays
(D) γ-rays

Answer

Ans -(D) γ-rays

5. Which of the following are not electromagnetic waves ?
(A) Gamma-rays
(B) B-rays
(C) X-rays
(D) Infrared-rays

Answer

Ans -(B) B-rays

6. Which of the following has highest frequency ?
(A) Ultraviolet rays
(B) Long radio waves
(C) Gamma rays
(D) X-rays

Answer

Ans – (C) Gamma rays

7. Which of the following has lowest wave-length ?
(A) Gamma rays
(B) X-rays
(C) Infrared rays
(D) Short radio waves

Answer

Ans – (A) Gamma rays

8. Which of the following has highest wave- length ?
(A) Gamma rays
(B) X-rays
(C) Ultraviolet rays
(D) Radio waves

Answer

Ans -(D) Radio waves

9. Which of the following has lowest frequency?
(A) Ultraviolet rays
(B) Long radio waves
(C) Gamma rays
(D) X-rays

Answer

Ans – (B) Long radio waves

10. What is the value of speed of γ-rays in vacuum?
(A) 2c
(B) c
(c) $\displaystyle \frac{c}{2}$
(D) $\displaystyle \frac{c}{{\sqrt{2}}}$

Answer

Ans -(B) c (Here c is speed of light in vaccum)

11. What is the value of speed of X-rays in vacuum?
(A) 2 c
(B) c
(C) $\displaystyle \frac{c}{2}$
(D) $\displaystyle \frac{c}{{\sqrt{2}}}$

Answer

Ans -(B) c

12. The wavelength of a wave with frequency 3×10⁹Hz will be:
(A) 0.1 m
(B) 1 m
(C) 10⁹ m
(D) 10^-2 m

Answer

Ans -(A) 0.1 m

13. The wavelength of a wave having frequency 3×10¹² Hz will be:
(A) 3×10⁸ m
(B) 3×10⁴ m
(C) 10^-4m
(D) 10⁴ m

Answer

Ans -The wavelength of a wave having frequency 3×10¹² Hz will be:

Chapter 9 Ray Optics and Optical Instruments

1. The angle of minimum deviation for a prism is 30° and the angle of prism is 60°. The refractive index of the material of the prism is :
(A) 2
(B) √2
(C) 1.5
(D) 1/√2

Answer

Ans -(B) √2

2. For yellow light incident on a prism of angle 60°, the angle of minimum deviation is 30°. The angle of incidence in this situation is :
(A) 30°
(B) 45°
(C) 60°
(D) 75°

Answer

Ans -(B) 45°

3. For a normal human eye the least distance of distinct vision is:
(A) 1 cm
(B) 2.5 cm
(C) 50 cm
(D) 25 cm

Answer

Ans -(D) 25 cm

4. Speed of Light in air is 3×10⁸ m/s. For the water of refractive Index 4/3, the speed of light will be:
(A) 1.5 x 10⁸ m/s
(B) 2×10⁸m/s
(C) 1×10⁸ m / s
(D) 2.25×10⁸ m/s

Answer

Ans – (D) 2.25×10⁸ m/s

5. Speed of light in air is 3 x 10⁸ m/s. For the glass of refractive index 1.5, speed of light in glass will be:
(A) 1.5 x 10⁸ m/s
(B) 2 x 10⁸ m/s
(C) 1 x 10⁸ m/s
(D) 2.5 x 10⁸ m/s

Answer

Ans – (B) 2 x 10⁸ m/s

6. Condition of minimum deviation for a Prism is:
(A) Angle of Incidence > Angle of Emergence
(B) Angle of Incidence = Angle of Emergence
(C) Angle of Incidence < Angle of Emergence
(D) None of the above

Answer

Ans -(B) Angle of Incidence = Angle of Emergence

7. Prism designed to bend light by 90° or 180° make use of :
(A) dispersion
(B) total internal reflection
(C) reflection
(D) diffraction

Answer

Ans -(B) total internal reflection

8. For small angle A prism (Refractive Index n), angle of Minimum deviation D_m is :
(A) $\displaystyle {{D}_{m}}=\frac{{n-1}}{A}$

(B) D_m = (n-1) A

(D) D_m =n-1

Answer

Ans -(B) D_m = (n-1) A

9. The angle of minimum deviation for a prism is δm and the angle of prism is A. The refractive index of the material of the prism is :

(A) $\displaystyle \sin \left( {\frac{{A+\delta m}}{2}} \right)$

(B) $\displaystyle \sin \frac{A}{2}$

(D) $\displaystyle \frac{{\sin \left( {\frac{{A+\delta m}}{2}} \right)}}{{\sin A/2}}$

Answer

Ans -(C) $\displaystyle \frac{{\sin A/2}}{{\sin \left( {\frac{{A+\delta m}}{2}} \right)}}$

10. The working of a totally reflecting prism is based upon :
(A) Total internal reflection
(B) Reflection
(C) Refraction
(D) None of these

Answer

Ans -(A) Total internal reflection

11. Optical fibres works on the phenomenon of:
(A) Dispersion
(B) Refraction
(C) Scattering
(D) Total Internal Reflection

Answer

Ans -(D) Total Internal Reflection

12. Mirage is a phenomena due to:
(A) Reflection
(B) Dispersion
(C) Scattering
(D) Total Internal Reflection

Answer

Ans – (D) Total Internal Reflection

13. Two lens of power 5D and – 3D are placed in contact. Focal length of the combination will be:
(A) 50 cm
(B) – 50 cm
(C) 25 cm
(D) – 25 cm

Answer

Ans -(A) 50 cm

14. The focal length of a lens of power +2D is :
(A) + 50cm
(B) – 50cm
(C) + 2 cm
(D) – 2 cm

Answer

Ans -(A) + 50cm

15. Two lens of power 8D and – 4D are placed in contact. Focal length of the combination will be:
(A) 50cm
(B) -50 cm
(C) 25 cm
(D) – 25cm

Answer

Ans -(C) 25 cm

16. The two Surfaces of a bi-convex Lens have equal radii of curvature R and its refractive Index n is 1.5. The focal Length of the Lens will be:
(A) R/2
(B) R
(C) -R
(D) 2R

Answer

Ans – (B) R

17. A thin convex lens of focal length 15 cm is placed in contact with a thin concave lens of focal length 15 cm. What is the power of the combination ?
(A) 0 D
(B) ∞ D
(C) 3D
(D) 6 D

Answer

Ans – (A) 0 D

18. A thin convex lens of focal length 10 cm is placed in contact with a thin concave lens of focal length 10 cm. What is the power of the combination ?
(A) ∞ D
(B) +5 D
(C) 0 D
(D) −5 D

Answer

Ans -(A) ∞ D

19. A thin convex lens of focal length 15 cm is placed in contact with a thin concave lens of focal length 10 cm. What is the focal length of the combination ?
(A) + 25 cm
(B) +5 cm
(C) – 30 cm
(D) – 5 cm

Answer

Ans – (C) – 30 cm

20. Double-convex lenses are to be manufactured from a glass of refractive index 1.5, with both faces of the same radius of curvature. If the focal length is to be 20 cm, radius of curvature required is:
(A) 10cm
(B) 15 cm
(c) 20 cm
(D) 30cm

Answer

Ans -(c) 20 cm

21. A thin convex lens of focal length 30 cm is placed in contact with a thin concave lens of focal length 20 cm. What is the focal length of the combination ?
(A) +50 cm
(B) -60 cm
(C) +10 cm
(D) -10 cm

Answer

Ans – (B) -60 cm

22. The focal length of a lens of power +4D is :
(A) – 25cm
(B) + 25 cm
(C) – 4 cm
(D) + 4 cm

Answer

Ans -(A) + 25cm

23. The focal length of a lens of power -4D is :
(A) + 25 cm
(B) + 4 cm
(C) – 25cm
(D) – 4 cm

Answer

Ans -(C) – 25cm

Chapter 10 Wave optics

1. The ratio of the intensities of two light waves is 16 : 9. The ratio of maximum and minimum intensities in their interference pattern will be:
(A) 4:3
(B) 49:1
(C) 25:7
(D) 256 : 81

Answer

Ans -(A) 4:3

2. In Young’s double slit experiment, the screen is moved away from the plane of the slits, angular separation of the Fringes:
(A) remain constant
(B) increases
(C) decreases
(D) interference pattern disappears

Answer

Ans -(C) decreases

3. In Young’s double slit experiment, the monochromatic source is replaced by another monochromatic source of shorter wavelength, then actual separation of the Fringes : Most Important
(A) remain constant
(B) increases
(C) decreases
(D) None of the above

Answer

Ans -(C) decreases

4. Which phenomenon illustrates particle nature of light waves?
(A) Interference
(B) Diffraction
(C) Polarization
(D) None of the above

Answer

Ans -(B) Diffraction

5. Which phenomenon illustrates the nature of light waves?
(A) Interference
(B) Diffraction
(C) Polarization
(D) None of the above

Answer

Ans -(A) Interference

6. Phenomenon of splitting of light into its constituent colours is known as:
(A) Scattering
(B) Diffraction
(C) Refraction
(D) Dispersion

Answer

Ans – (D) Dispersion

7. Two light waves of equal amplitude and wave length are super imposed. The amplitude of the resultant wave will be maximum when the phase difference between them is :
(A) Zero
(B) π/2
(C) π
(D) π/4

Answer

Ans -(A) Zero

Chapter 11 Dual Nature of Radiations and Matter

1. The charge on an electron is:
(A) 0 C
(B) 1 C
(C) -2.6 x 10^-19 C
(D) -1.6 x 10^-19 C

Answer

Ans -(D) -1.6 x 10^-19 C

2. The charge on an Proton is :
(A) 0 C
(B) 1 C
(C) – 2.6 × 10⁺¹⁹ C
(D) + 1.6 x 10^-19 C

Answer

Ans – (D) + 1.6 x 10^-19 C

3. In 1905, which scientist proposed a radically new picture of electromagnetic radiation to explain photoelectric effect?
(A) Millikan
(B) Einstein
(C) Rutherford
(D) Compton

Answer

Ans – (B) Einstein

4. Which scientist verified Einstein’s photoelectric equation with great precision, for a number of alkali metals over a wide range of radiation frequencies?
(A) Millikan
(B) Einstein
(C) Rutherford
(D) Compton

Answer

Ans – (A) Millikan

5. Awarded the Nobel prize in physics for his contribution to theoretical physics and the photoelectric effect in 1921 was :
(A) Millikan
(B) Einstein
(C) Rutherford
(D) Compton

Answer

Ans – (B) Einstein

6. The stopping potential for photoelectrons depends upon :
(A) Frequency of incident light only
(B) Material of the cathode only
(C) Both the frequency of incident light and the material of the cathode
(D) Intensity of incident light

Answer

Ans -(A) Frequency of incident light only

7. Electron emission from a metallic surface is possible only, when Frequency of the incident Light is :
(A) Less Then threshold Frequency
(B) Half of the Threshold Frequency
(C) Greater than the Threshold Frequency
(D) No effect of Frequency

Answer

Ans -(C) Greater than the Threshold Frequency

8. Electron emission from a metallic surface is possible only, when wavelength of the incident light is:
(A) less than threshold wavelength
(B) twice of the threshold wavelength
(C) greater than the threshold wavelength
(D) no effect of wavelength

Answer

Ans -(A) less than threshold wavelength

9. Which of the following has minimum stopping potential?
(A) Blue
(B) Yellow
(C) Voilet
(D) Red

Answer

Ans -(D) Red

10. For which of the following stopping potential required is maximum ?
(A) Red
(B) Green
(C) Yellow
(D) Blue

Answer

Ans -(D) Blue

11. The electrons ejected from metals due to effect of light are called:
(A) Primary electrons
(B) Secondary electrons
(C) Photo electrons
(D) Thermions.

Answer

Ans -(C) Photo electrons

Chapter 12 Atoms

1. The energy of an atom in ground state is -4.9 eV. The ionisation energy of this atom is :
(A) 2.45 eV
(B) 13.6 eV
(C) 9.8 eV
(D) 4.9 eV

Answer

Ans -(D) 4.9 eV

2. Whose model of atom is also called nuclear model of atom ?
(A) Thomson
(B) Rutherford
(C) de Broglie
(D) Bohr

Answer

Ans – (B) Rutherford

3. The charge on an atom is :
(A) 0 C
(B) 1 C
(C) – 1.6 x 10⁺¹⁹ C
(D) 1.6 × 10^-19 C

Answer

Ans – (A) 0 C

4. According to Rutherford’s experiments, the size of nucleus is about:
(A) 10^-11 m to 10^-10 m
(B) 10^-13 m to10^-12 m
(C) 10^-15 m to10^-14 m
(D) 10^-12 m to10^-11 m

Answer

Ans – (C) 10^-15 m to 10^-14 m

5. In hydrogen atom, the potential energy of electron in an orbit of radius r is given by :

(A) $\displaystyle -\frac{1}{{4\pi {{\in }_{0}}}}.\frac{{{{e}^{2}}}}{r}$

(B) $\displaystyle \frac{1}{{4\pi {{\in }_{0}}}}.\frac{{{{e}^{2}}}}{{2r}}$

(D) $\displaystyle -\frac{1}{{4\pi {{\in }_{0}}}}.\frac{{{{e}^{2}}}}{{2r}}$

Answer

Ans -(A) $\displaystyle -\frac{1}{{4\pi {{\in }_{0}}}}.\frac{{{{e}^{2}}}}{r}$

6. In hydrogen atom, the Kinetic energy of electron in an orbit of radius r is given by:

(A) $\displaystyle -\frac{1}{{4\pi {{\in }_{0}}}}.\frac{{{{e}^{2}}}}{r}$

(B) $\displaystyle \frac{1}{{4\pi {{\in }_{0}}}}.\frac{{{{e}^{2}}}}{{2r}}$

(D) $\displaystyle -\frac{1}{{4\pi {{\in }_{0}}}}.\frac{{{{e}^{2}}}}{{2r}}$

Answer

Ans -(B) $\displaystyle \frac{1}{{4\pi {{\in }_{0}}}}.\frac{{{{e}^{2}}}}{{2r}}$

7. The total energy of an electron in the first excited state of the hydrogen atom is about -3.4 eV. Kinetic energy of the electron in this state is :
(A) -3.4 eV
(B) 6.8 eV
(C) -6.8 eV
(D) 3.4 eV

Answer

Ans -(D) 3.4 eV

8. The total energy of an electron in the first excited state of the hydrogen atom is about -3.4 eV. Potential energy of the electron in this state is :
(A) – 3.4 eV
(B) 6.8 eV
(C) -6.8 eV
(D) -1.7 eV

Answer

Ans -(C) -6.8 eV

9. The ground state total energy of hydrogen atom is about -13.6 eV. Kinetic energy of the electron in this state is:
(A) – 13.6 eV
(B) 13.6 eV
(C) – 27.2 eV
(D) 27.2 eV

Answer

Ans -(B) 13.6 eV

10. The ionization energy of hydrogen atom is:
(A) 13.6 J
(B) 13.6 eV
(C) 1 eV
(D) 10.2 eV

Answer

Ans -(B) 13.6 eV

11. Which spectral series of hydrogen atom lies in the ultraviolet region ?
(A) Lyman
(B) Balmer
(C) Paschen
(D) Brackett

Answer

Ans -(A) Lyman

12. Which spectral series does not lie in the spectrum of hydrogen atom ?
(A) Special
(B) Lyman
(C) Balmar
(D) Paschen

Answer

Ans -(A) Special

13. Which spectral series of hydrogen atom lie in the visible region?
(A) Lyman
(B) Paschen
(C) Pfund
(D) Balmer

Answer

Ans -(D) Balmer

14. Which spectral series of hydrogen atom lie in the infrared region ?
(A) Lyman
(B) Paschen
(C) Balmer
(D) None of these

Answer

Ans -(B) Paschen

15. The de-Broglie wavelength associated with a moving particle is :
(A) directly proportional to its mass
(B) inversely proportional to its mass
(C) directly proportional to its energy
(D) directly proportional to its momentum

Answer

Ans -(D) directly proportional to its momentum

16. Who discovered the nucleus ?
(A) Thomson
(B) Bohr
(C) Rutherford
(D) de Broglie

Answer

Ans – (C) Rutherford

17. Which model of atom suggests that atom is a spherical cloud of positive charges with electrons embedded in it ?
(A) Rutherford model
(B) Bohr model
(C) Thomson model
(D) de Broglie

Answer

Ans – (C) Thomson model

18. de-Broglie wavelength associated with an electron, accelerated through a potential difference of V volt is:
(A) (1227/ √V) Å
(B) ( 1.227/ √V ) Å
(C) ( 12.27 /√V ) Å
(D) ( 122.7 /√V ) Å

Answer

Ans -(C) ( 12.27 /√V ) Å

19. A de-Broglie wavelength associated with an electron, accelerated through a potential difference of 100 Volt is :
(A) 1.127 Å
(B) 11.27 Å
(C) 12.27 Å
(D) 1.227 Å

Answer

Ans -(D) 1.227 Å

20. de-Broglie wavelength associated with an electron, accelerated through a potential difference of 100 Volt is :
(A) .1127 nm
(B) 1.127 nm
(C) .127 nm
(D) .1227 nm

Answer

Ans -(D) .1227 nm

21. The de Broglie wavelength associated with an electron accelerated through a potential difference of 64 V is:
(A) 1.227 nm
(B) 0.153 nm
(C) 1.53 nm
(D) 12.27 nm

Answer

Ans -(B) 0.153 nm

22. The de Broglie wavelength associated with an electron accelerated through a potential difference of 121 V is:
(A) 1.227 nm
(B) 12.270 nm
(C) 0.112 nm
(D) 11.200 nm

Answer

Ans -(C) 0.112 nm

23. An electron is moving under a potential difference of 1 volt, what will be the de-Broglie wavelength?
(A) 1 m
(B) 1.227 m
(C) 12.27 Å
(D) 1.227 Å

Answer

Ans -(C) 12.27 Å

24. What is the de-Broglie wavelength associated with an electron moving under a potential difference of 10⁴ volts will be :
(A) 1m
(B) 12.27 Å
(C) 0.1227 Å
(D) 1.227 m

Answer

Ans -(C) 0.1227 Å

25. de-Broglie wavelength associated with an electron moving under a potential difference of 150 volts will be:
(A) 12.27 Å
(B) 1 Å
(C) 1.227 Å
(D) 1 m

Answer

Ans -(C) 1.227 Å

Chapter 13 Nuclei

1. A positively charged body has in it:
(A) Excess of Neutrons
(B) Excess of Electrons
(C) Deficiency of Electrons
(D) Deficiency of Protons.

Answer

Ans -(C) Deficiency of Electrons

2. A negatively charged body has in it:
(A) Excess of Neutrons
(B) Excess of Electrons
(C) Deficiency of Electrons
(D) Excess of Protons

Answer

Ans -(B) Excess of Electrons

3. Number and type of nucleons in the nucleus of Deuterium (₁H²) will be:
(A) 2 protons
(B) 1 proton and 1 neutron
(C) 2 neutrons
(D) 1 proton and 1 electron

Answer

Ans – (B) 1 proton and 1 neutron

4. Two atoms have the same atomic number but different atomic mass. They will be:
(A) Isotopes
(B) Isobaric
(C) Isotones
(D) None of these

Answer

Ans -(A) Isotopes

5. All nuclides with same mass number A are called:
(A) Isobars
(B) Isotones
(C) Isotopes
(D) All of the above.

Answer

Ans -(A) Isobars

6. All nuclides with same Atomic number Z are called:
(A) Isobars
(B) Isotones
(C) Isotopes
(D) None of the above.

Answer

Ans -(C) Isotopes

7. Nuclides with same neutron number N but different atomic number Z are called :
(A) Isobars
(B) Isotones
(C) Isotopes
(D) None of the above

Answer

Ans -(B) Isotones

8. Number and type of nucleons in the nucleus of Helium ( ₂He⁴ ) will be :
(A) 2 protons
(B) 2 protons and 2 neutrons
(C) 2 protons and 2 electrons
(D) 2 neutrons

Answer

Ans -(B) 2 protons and 2 neutrons

9. The charge on a neutron is:
(A) 0 C
(B) 1.6 x 10^-19 C
(C) – 1.6 x 10^-19 C
(D) 1 C

Answer

Ans – (A) 0 C

Chapter 14 Semiconductor Electronics : Materials, Devices and Simple Circuits

1. At absolute zero temperature, a crystal of pure germanium behaves as:
(A) a perfect conductor
(B) a perfect insulator
(C) a semiconductor
(D) None of these

Answer

Ans -(B) a perfect insulator

2. In intrinsic semiconductor at room temperature, the numbers of electrons and holes are :
(A) Equal
(B) Zero
(C) Unequal
(D) Infinite

Answer

Ans -(A) Equal

3. In a p-type semiconductor the minority charge carriers are:
(A) Electron
(B) Hole
(C) Electron and Hole
(D) None of these

Answer

Ans -(A) Electron

4. Which dopant cannot be used to make silicon (Si) a p-type semi-conductor ?
(A) In
(B) Al
(C) B
(D) P

Answer

Ans – (D) P

5. Which dopant cannot be used to make Germanium (Ge) a p-type semiconductor?
(A) P
(B) In
(C) B
(D) Al

Answer

Ans -(B) In

6. In a n-type Semi Conductor the minority charge carriers are:
(A) Electron
(B) Hole
(C) Electron and hole
(D) None of these

Answer

Ans -(B) Hole

7. Which dopant cannot be used to make Germanium (Ge) an n-type semiconductor ?
(A) P
(B) In
(C) As
(D) Sb

Answer

Ans -(B) In

8. Which dopant cannot be used to make silicon (Si) an n-type semi-conductor ?
(A) B
(B) As
(C) P
(D) Sb

Answer

Ans -(A) B

9. When a forward biased is applied to a p-n junction, it :
(A) Raises the potential barrier
(B) Reduces the majority carrier current to zero
(C) Lowers the potential barrier
(D) None of the above

Answer

Ans -(C) Lowers the potential barrier

10. When a reverse biased is applied to a p-n junction, it :
(A) Raises the potential barrier
(B) Increases the majority carrier current
(C) Lowers the potential barrier
(D) None of the above.

Answer

Ans -(A) Raises the potential barrier

11. In an unbiased p-n junction, holes diffuse from the p-region to n-region, because :
(A) Free electron in the n-region attract them
(B) They move across the junction by the potential difference
(C) Hole concentration in p-region is more as compared to n-region
(D) All of the above

Answer

Ans -(C) Hole concentration in p-region is more as compared to n-region

12. Energy band of substance shown in the figure where V is valence band and C is conduction band:

Substance is : Most important
(A) Metal
(B) Semiconductor
(C) Insulator
(D) None of the above

Answer

Ans -(C) Insulator

13. Energy band of a substance is shown in Figure. Where V is valence band and C is conduction band.

This substance is :
(A) Conductor
(B) Semi conductor
(C) Insulator
(D) Diamond

Answer

Ans -(B) Semi conductor

14. Carbon, silicon and germanium have four valence electrons each. These are characterized by valence band and conduction bands separated by energy band gap respectively equal to (E_g)_c , (E_g)_si and (E_g)_Ge . Which of the following statement is true?
(A) (E_g) si < ((E_g)_Ge < (E_g)_c
(B) (E_g)_c < (E_g)_Ge > (E_g)_si
(C) (Eg)_c > (E_g)_si > (E_g)_Ge
(D) (E_g)_c = (E_g)_si = (E_g)_Ge

Answer

Ans -(C) (Eg)_c > (E_g)_si > (E_g)_Ge

HBSE Class 12 Physics MCQ Important Question Answer 2024

HBSE Class 12 Physics Important MCQ Question Answer 2024

Chapter 1 Electric Charges and Fields

Chapter 2 Electrostatic Potential and Capacitance

Chapter 3 Current Electricity

Chapter 4 Moving Charges and Magnetism

Chapter 5 Magnetism and Matter

Chapter 6 Electromagnetic Induction

Chapter 7 Alternating Current

Chapter 8 Electromagnetic Waves

Chapter 9 Ray Optics and Optical Instruments

Chapter 10 Wave optics

Chapter 11 Dual Nature of Radiations and Matter

Chapter 12 Atoms

Chapter 13 Nuclei

Chapter 14 Semiconductor Electronics : Materials, Devices and Simple Circuits

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HBSE Class 12 Physics Important MCQ Question Answer 2024

Chapter 1 Electric Charges and Fields

Chapter 2 Electrostatic Potential and Capacitance

Chapter 3 Current Electricity

Chapter 4 Moving Charges and Magnetism

Chapter 5 Magnetism and Matter

Chapter 6 Electromagnetic Induction

Chapter 7 Alternating Current

Chapter 8 Electromagnetic Waves

Chapter 9 Ray Optics and Optical Instruments

Chapter 10 Wave optics

Chapter 11 Dual Nature of Radiations and Matter

Chapter 12 Atoms

Chapter 13 Nuclei

Chapter 14 Semiconductor Electronics : Materials, Devices and Simple Circuits

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