Question

Assertion : In YDSE bright and dark fringe are equally spaced.
Reason : It only depends upon phase difference.

• A. If both assertion and reason are true and reason is the correct explanation of assertion.
• B. If both assertion and reason are true but reason is not the correct explanation of assertion.
• C. If assertion is true but reason is false.
• D. If both assertion and reason are false.

Answer 1

Answer: (C)

Fringe width is given by, $\beta=\frac{D\lambda}{d}$
where, D = distance between stil and screen,
d = distance between coherent sources of light
and $\lambda$ = wavelength of incident light.