Assertion (A) : For best contrast between maxima and minima in the interference pattern of Young's double slit experiment the intensity of light emerging out of the two slits should be equal.
Reasson (R ) : The intensity of interference pattern is proportional to the square of the amplitude.

Options

A. (a) If both assertion and reason are true and reason is the correct explanation of assertion.
B. (b) If both assertion and reason are true but reason is not the correct explanation of assertion.
C. (c) If assertion is true but reason is false.
D. (d) If assertion and reason both are false.

Answer

B

Explanation

When intensity of light emerging from two slits is equal, the intensity at minima,
`I_(min)=(sqrt(I_a)-sqrt(I_b))^2=0`, or absolute dark.
It provides a better contrast.