A source of light is placed at a distance of \(50\) cm from a photocell and the stopping potential is found to be \(V_0\). If the distance between the light source and photocell is made \(25\) cm, the new stopping potential will be: 

1.	\(V_0 /2\)	2.	\(V_0 \)
3.	\(4V_0 \)	4.	\(2V_0 \)

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, the number of emitted electrons and their maximum kinetic energy are respectively:

1. 2N and T

2. 2N and 2T

3. N and T

4. N and 2T

The threshold frequency for a photosensitive metal is \(3.3\times10^{14}~\text{Hz}.\) If the light of frequency \(8.2\times10^{14}~\text{Hz}\) is incident on this metal, the cutoff voltage for the photoelectric emission will be:

If the momentum of an electron is changed by \(p,\) then the de-Broglie wavelength associated with it changes by \(0.5\%.\) The initial momentum of an electron will be:
1. \(400p\)
2. \(\frac{p}{100}\)
3. \(100p\)
4. \(200p\)

Two radiations of photons energies \(1\) eV and \(2.5\) eV, successively illuminate a photosensitive metallic surface of work function \(0.5\) eV. The ratio of the maximum speeds of the emitted electrons is:
1. \(1:2\)
2. \(1:1\)
3. \(1:5\) 
4. \(1:4\)

The momentum of a photon of energy 1 MeV in kg m/s, will be:

1. $0.33\times {10}^6$

2. $7\times {10}^{-24}$

3. ${10}^{-22}$

4. $5\times {10}^{-22}$

When photons of energy h$\nu$ fall on an aluminium plate (of work function E₀), photoelectrons of maximum kinetic energy K are ejected. If the frequency of the radiation is doubled, the maximum kinetic energy of the ejected photoelectrons will be:

1. $K+E_0$

2. 2K

3. K

4. K+h$\nu$

A photocell employs a photo-electric effect to convert:

Monochromatic light of frequency 6.0×10¹⁴ Hz is produced by a laser. The power emitted is 2×10^-3 W. The number of photons emitted, on average, by the source per second is:

1. $5\times {10}^{15}$

2. $5\times {10}^{16}$

3. $5\times {10}^{17}$

4. $5\times {10}^{14}$