Q 12-10-012NEETJEE MainEasy
In Young's double slit experiment the slit separation is $0.5$ mm, the screen is $1$ m away and the wavelength is $500$ nm. The fringe width is
Answer: (A) $1$ mm
Concept. $\beta = \dfrac{\lambda D}{d}$.
Step 1. Substitute.
$$\beta = \frac{500 \times 10^{-9} \times 1}{0.5 \times 10^{-3}} = 10^{-3}\ \text{m} = 1\ \text{mm}$$
Answer. $1$ mm (Option A).
Solution by Sreeraj P, M.Sc Physics