Question

In an experiment using Young?s double slit, what will be the value of fringe width $\beta$ , if the wavelength is doubled?

• A. $\beta$
• B. $2\beta$
• C. $\beta/2$
• D. $4\beta$

Answer 1

Answer: (B)

$2\beta$

Answer 2

Fringe width, $\beta=\frac{\lambda D}{d}$
If $\lambda$ is doubled, $\beta$ will become $2\beta$