Question

Let $p$ and $E$ denote the linear momentum and the energy of a photon. For another photon of smaller wavelength (in same medium)

• A. Both $p$ and $E$ increase
• B. $p$ increases and $E$ decreases
• C. $p$ decreases and $E$ increases
• D. Both $p$ and $E$ decrease

Answer 1

The correct option is A Both $p$ and $E$ increase

De-Broglie relation:

$p=\frac{h}{\lambda }$

and from Planks relation:

$E=\frac{hc}{\lambda }$

Therefore, as $\lambda$ increases, both p and E increase.