The pressure exerted by an electromagnetic wave of intensity I( W / m 2) on a non-reflecting surface is [c is the velocity of light]

Question

The pressure exerted by an electromagnetic wave of intensity I( W / m 2) on a non-reflecting surface is [c is the velocity of light] (A) I / c (B) I c2 (C) I c (D) I / c2

Tardigrade Admin · Accepted Answer

When a surface intercepts electromagnetic radiation, a force and a pressure are exerted on the surface.
As the surface is non-reflecting, so, it is completely absorbed and in such case the force is

F = \frac{I A}{c}

where

I

is intensity of light.

A

is area of surface and

c

is velocity of electromagnetic wave.
The radiation pressure is the force per unit area
i.e.,

P = \frac{F}{A} = \frac{I}{c}

Q. The pressure exerted by an electromagnetic wave of intensity $I (W / m^{2})$ on a non-reflecting surface is $[c$ is the velocity of light]

$I / c$

$I c^{2}$

$I c$

$I / c^{2}$

Q. The pressure exerted by an electromagnetic wave of intensity I(W/m2) on a non-reflecting surface is [c is the velocity of light]

I/c

Ic2

Ic

I/c2

Q. The pressure exerted by an electromagnetic wave of intensity $I (W / m^{2})$ on a non-reflecting surface is $[c$ is the velocity of light]

$I / c$

$I c^{2}$

$I c$

$I / c^{2}$