# Physics Class-12 Chapter-11 Radiation And Dual Nature Of Matter Most VVI Objective Questions

Q.1. Which of the following has the dimensions of planck’s constant ?

(A) force Time

(B) force distance

(C) force speed

(D) force distance time

Ans:- (D)

Q.2. The energy (E) of photon is

(A) hv

(B) hv/c

(C) 1/2mv

(D) h/p

Ans:- (A)

Q.3. The SI unit of planck’s constant is

(A) Js

(B) Ws

(C) Js⁻¹

(D) Js⁻²

Ans:- (A)

Q.4. Electron volt (eV) is the measure of

(A) charge

(B) potential difference

(C) current

(D) energy

Ans:- (D)

Q.5. Dimension of planck’s constant

(A) ML²T⁻¹

(B) ML²T⁻²

(C) MLT⁻¹

(D)MLT⁻²

Ans:- (A)

Q.6. On the basis of photoelectric effect light is

(A) Wave

(B) Particle

(C) Both

(D) None of these

Ans:- (B)

Q.7. The energy of emitted photoelectrons depends up on

(A) intensity of light

(B) Wave length of light

(C) Work function of metal

(D) None of these

Ans:- (B)

Q.8. The hypothesis of matter wave was given by

(A) plank

(B) Thomson

(C) Einstein

(D) de broglie

Ans:- (D)

Q.9. Photoelectric effect occurs due to

(A) wave nature of light

(B) particle nature of light

(C) both A and B

(D) None of these

Ans:- (B)

Q.10. X- rays are made up of

(A) negatively charged particles

(B) positively charged particles

(D) neutrons

Ans:- (C)

Q.11. The maximum kinetic energy of photoelectrons emitted in photoelectric effect depends linearly upon

(A) Square frequency of incident light

(B) frequency of incident light

(C) wavelength of incident light

(D) square of wavelength of incident light

Ans:- (B)

Q.12. Name the experiment which verified de Broglie’s relation

(A) Machelson’s interferometer

(B) photoelectric effect

(C) Davisson and Germer

(D) None of these

Ans:- (C)

Q.13. When a photon stimulates the  emission of another Photon, the two photons have

(A) same energy

(B) same direction

(C) same wavelength

(D) all of above

Ans:- (D)

Q.14. Photoelectric effect reveals the

(C) both A and B

Ans:- (B)

Q.15. On which principle photocell is based

(A) compton effect

(B) Photoelectric effect

(C) electrolysis

(D) None of these

Ans:- (B)

Q.16. Photo cell is converted

(A) mechanical energy into electrical energy

(B) Electrical energy into light energy

(C) light energy into electrical energy

(D) electrical energy into mechanical energy

Ans:- (C)

Q.17. The discovery of Photoelectric effect is first observed by

(A) Einstein

(B) Heinrich Hertz

(C) J J Thomson

(D) None of these

Ans:- (B)

Q.18. If particles are moving with same velocity, then which has maximum de Broglie wavelength ?

(A) proton

(B) α-particke

(C) neutron

(D) β-particke

Ans:- (D)

Q.19. The de Broglie wavelength of a moving particle becomes larger if it’s

(A) mass is increased

(B) momentum is reduced

(C) momentum is increased

(D) velocity is increased

Ans:- (B)

Q.20. Which Photon is more energic:- A red one or a violet one ?

(A) Violet

(B) red

(C) both A and  B

(D) none of these

Ans:- (A)

Q.21. A photon travels with the speed of light in vacuum and has

(A) charge and no rest mass

(B) both charge and rest mass

(C) no charge and no rest mass

(D) none of these

Ans:- (C)

Q.22. What is the rest mass of photon ?

(A) Infinity

(B) equal to mass of electron

(C) Zero

(D) none of these

Ans:- (C)

Q.23. The energy of a photon of green light of wavelength 5500 Angstrom

(A) 2.20eV

(B) 2.0eV

(C) 2.25eV

(D) 2.3eV

Ans:- (C)

Q.24. What is the minimum value of compton shift ?

(A) zero

(B) 2h/m₀C

(C) m₀C/2h

(D) none of these

Ans:- (A)

Q.25. What is the momentum of a photon of frequency v

(A) hv/C

(B) C/hv

(C) h/c

(D) none of these

Ans:- (A)