Fresnel diffraction is produced due to light rays falling on a small obstacle. The intensity of light at a point on a screen beyond an obstacle depends on

Options

A. The focal length of lens used for observation
B. The number of half-period zones that superpose at the point
C. The square of the sum of the number of half period of zones
D. The thickness of the obstacle

Answer

B

Explanation

The intensity of light at a point on screen depends on number of half period zones.