The figure shows a plot of photocurrent versus anode potential for a photosensitive surface for three different radiations. Which one of the following is a correct statement?
        

1.	Curves \(a\) and \(b\) represent incident radiations of different frequencies and different intensities.
2.	Curves \(a\) and \(b\) represent incident radiation of the same frequency but of different intensities.
3.	Curves \(b\) and \(c\) represent incident radiation of different frequencies and different intensities.
4.	Curves \(b\) and \(c\) represent incident radiations of the same frequency having the same intensity.

A particle of mass \(1\) mg has the same wavelength as an electron moving with a velocity of  \(3\times 10^{6}\) ms^-1. The velocity of the particle is:
(Mass of electron = \(9.1 \times 10^{-31}\) kg)
1. \(2.7 \times 10^{-18}~\text{ms}^{-1}\)
2. \(9 \times 10^{-2}~\text{ms}^{-1}\)
3. \(3 \times 10^{-31}~\text{ms}^{-1}\)
4. \(2.7 \times 10^{-21}~\text{ms}^{-1}\)

A \(5\) W emits monochromatic light of wavelength \(5000~\mathring{A}\). When placed \(0.5\) m away, it liberates photoelectrons from a photosensitive metallic surface. When the source is moved \(1.0\) m away, the number of photoelectrons liberated is reduced by a factor of?
1. \(4\)
2. \(8\)
3. \(16\)
4. \(2\)

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. $5\times {10}^{14}$

A photocell employs a photo-electric effect to convert:

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$\nu$

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. $5\times {10}^{-22}$