10 Question-answer on Wave nature of particle (de-broglie wave)
1. A proton and alpha particle are accelerated through the same potential difference. The ratio of their de-Broglie wavelength will be:
(a) 1:1
(b) 1:2
(c) 2:1
(d) 2√2:1
Ans: (d)
2. A particle with rest mass m0 is moving with speed of light c. the de-Broglie wavelength associated with it will be:
(a) ∞
(b) Zero
(c) M0c/h
(d) Hv/m0c.
Ans: ( b)
3. The ratio of wavelengths of proton and deuteron accelerated through the same potential difference will be:
(a) 1:2
(b) 2:1
(c) √2:1
(d) 1:√2
Ans: ( c)
4. Through what potential difference should an electron be accelerated so that its de-Broglie wavelength becomes 0.5 A
(a) 6022 V
(b) 602.2 V
(c) 60.22 V
(d) 6.022 V
Ans: (b)
5. If and p are the energy and the momentum of a photon respectively then on increasing the wavelength of photon
(a) P and E both will decreases
(b) P and E both will increases
(c) P will increases and E will decreases
(d) P will decrease and E will increase
Ans: (a)
6. If a photon and an electron have same de-Broglie wavelength, then
(a) Both have same kinetic energies
(b) Proton has more K.E. than electron
(c) Electron has more K.E. than proton
(d) Both have same velocity
Ans: ( c)
7. An electron and proton are moving with the same speed. Mass of proton = 1836 times mass of electron. The ratio of their de-Broglie wavelengths will be
(a) 1
(b) 1836
(c) 1/1836
(d) 918
Ans: (b)
8. Dual nature of radiation is shown by
(a) Diffraction and reflection
(b) Refraction and diffraction
(c) Photoelectric effect alone
(d) Photoelectric effect and diffraction
Ans: (d)
9. What should be the velocity of an electron so that its momentum becomes equal to that of a photon of wavelength 5200 A?
(a) 700 m/s
(b) 1000 m/s
(c) 1400 m/s
(d) 2800 m/s
Ans: ( c)
10. Which of the following pairs of phenomena illustrates the particular aspect of wave-particle duality?
(a) Compton effect and Bragg’s law
(b) Photoelectric effect and Compton effect
(c) Compton effect and Pauli’s principle
(d) Bragg’s law and photoelectric effect.
Ans: ( a, d)