JEE Main & Advanced
Physics
Photo Electric Effect, X- Rays & Matter Waves
Question Bank
Photon and Photoelectric Effect
question_answer
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 [AMU (Engg.) 2001]
A) Energy and momentum
B) Speed and momentum
C) Speed only
D) Energy only
Correct Answer:
C
Solution :
Speed of photon is \[3\times {{10}^{8}}m/s\] in vacuum.