If c is the velocity of light in free space, the correct statements about photons among the following are:
(A)

Question

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 = hν.
(B) The velocity of a photon is c.
(C) The momentum of a photon, p = hν/c.
(D) In a photon-electron collision, both total energy and total momentum are conserved.
(E) Photon possesses a positive electric charge.

Accepted Answer

Let's analyze each statement:
(A) **Correct:** The energy of a photon is given by Planck's equation $E = h
u$ .
(B) **Correct:** In vacuum, all electromagnetic radiation (photons) travels at the speed of light, $c$ .
(C) **Correct:** Using de Broglie's relation $\lambda = h/p$ and the wave equation $c = 
u\lambda$, we substitute $\lambda = c/
u$ to get $c/
u = h/p$, which rearranges to $p = h
u/c$ .
(D) **Correct:** In collisions between particles (like photon-electron collisions), the fundamental laws of conservation of total energy and total momentum hold true , .
(E) **Incorrect:** Photons are electrically neutral particles; they do not possess an electric charge (unlike alpha particles or protons) .

Thus, statements (A), (B), (C), and (D) are correct.

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