Which of the following figures represents the variation of the particle momentum and the associated de-Broglie wavelength?
1. | 2. | ||
3. | 4. |
A photoelectric surface is illuminated successively by monochromatic light of wavelengths λ and λ/2. If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case, the work function of the surface of the material will be:
(h = Planck’s constant, c = speed of light)
1. hc/2λ
2. hc/λ
3. 2hc/λ
4. hc/3λ
Light with a wavelength of 500 nm is incident on a metal with a work function of 2.28 eV. The de Broglie wavelength of the emitted electron will be:
1. \( <2.8 \times 10^{-10} \mathrm{~m} \)
2. \( <2.8 \times 10^{-9} \mathrm{~m} \)
3. \( \geq 2.8 \times 10^{-9} \mathrm{~m} \)
4. \( <2.8 \times 10^{-12} \mathrm{~m}\)
What will be the percentage change in the de-Broglie wavelength of the particle if the kinetic energy of the particle is increased to 16 times its previous value?
1. 25
2. 75
3. 60
4. 50
If the momentum of an electron is changed by p, then the de-Broglie wavelength associated with it changes by 0.5%. What is the initial momentum of the electron?
1. 200p
2. 400p
3.
4. 100p
When monochromatic radiation of intensity I falls on a metal surface, the number of photoelectrons and their maximum kinetic energy are N and T respectively. If the intensity of radiation is 2I what is the number of emitted electrons and their maximum kinetic energy?
1. | N and 2T | 2. | 2N and T |
3. | 2N and 2T | 4. | N and T |
A helium-neon laser produces monochromatic light of a wavelength of 667 nm. The power emitted is 9 mW. The average number of photons arriving per second on average at a target irradiated by this beam is:
1.
2.
3.
4.
Waves are associated with matter only:
1. | When it is stationary. |
2. | When it is in motion with the velocity of light only. |
3. | When it is in motion with any velocity. |
4. | None of the above. |
A particle which has zero rest mass and non-zero energy and momentum must travel with a speed:
1. | Equal to c, the speed of light in vacuum. |
2. | Greater than c. |
3. | Less than c. |
4. | Tending to infinity. |
If the following particles are moving at the same velocity, then which among them will have the maximum de-Broglie wavelength?
1. Neutron
2. Proton
3. -particle
4. -particle