Q. According to photon theory of light which of the following physical quantities associated with a photon do not/does not change as it collides with an electron in vacuum
A) Energy and momentum
B) Speed and momentum
C) Speed only
D) Energy only
Explanation
(c) Speed of photon is $3 \times 10^{8}m/s$ in vacuum
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.