In a single-slit diffraction setup, slit width 0.2 mm, screen distance…

Question

In a single-slit diffraction setup, slit width 0.2 mm, screen distance 2 m. First minimum is observed at 5 mm from the central maximum. The wavelength of light is:

Accepted Answer

D. Both A and C

First minimum: $y = D\lambda/a$. So $\lambda = ya/D = (5	imes10^{-3})(0.2	imes10^{-3})/2 = 5 	imes 10^{-7}$ m = 500 nm = 5000 Å.

Answer

500 nm

Answer

550 nm

Answer

5000 Å (= 500 nm)