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. $\frac{\mathrm{p}}{200}$

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?

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. $9\times {10}^{17}$

2. $3\times {10}^{16}$

3. $9\times {10}^{15}$

4. $3\times {10}^{19}$

Waves are associated with matter only:

A particle which has zero rest mass and non-zero energy and momentum must travel with a speed:

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. $\mathrm{\beta }$-particle             

4. $\mathrm{\alpha }$-particle

What is the momentum of a photon in an X-ray beam of 10^-10 meter wavelength?

The energy of a quanta of frequency ${10}^{15}$ Hz and $\mathrm{h}=6.6\times {10}^{-34}\mathrm{ J}-\sec$ will be:

1. $6.6\times {10}^{-19}$ $\mathrm{J}$

$\mathrm{}$2.$6.6\times {10}^{-12}$ $\mathrm{J}$

3. $6.6\times {10}^{-49}$ $\mathrm{J}$

$\mathrm{}$4.$6.6\times {10}^{-41}$ $\mathrm{J}$

The number of photo-electrons emitted per second from a metal surface increases when: