If \(c\) is the velocity of light in free space, the correct statements about photons among the following are:
(A) | The energy of a photon is \(E=h\nu.\) |
(B) | The velocity of a photon is \(c.\) |
(C) | The momentum of a photon, \(p={\dfrac{h\nu}{c}}.\) |
(D) | In a photon-electron collision, both total energy and total momentum are conserved. |
(E) | Photon possesses a positive electric charge. |
1. | (A), (B), (C) and (D) only |
2. | (A), (C) and (D) only |
3. | (A), (B), (D) and (E) only |
4. | (A) and (B) only |
The number of photons per second on an average emitted by a source of monochromatic light of wavelength \(600~\text{nm}\), when it delivers the power of \(3.3\times 10^{-3}\) watt will be:
\((h = 6.6\times10^{-34}~\text{J-s})\)
1. | \(10^{16}\) | 2. | \(10^{15}\) |
3. | \(10^{18}\) | 4. | \(10^{17}\) |