Question

A student performing a double-slit experiment is using a green laser with a wavelength of 550 nm. She is confused when the m = 5 maximum does not appear. She had predicted that this bright fringe would be 1.6 cm from the central maximum on a screen 1.5 m behind the slits. What is the width of her slits?

Answer 1

Answer:

d = 52 μm

Explanation:

given,

wavelength of the light source (λ)= 550 nm

distance to form interference pattern(D) = 1.5 m

y = 1.6 cm = 0.016 m

width of the slits = ?

now, using displacement formula

 $y = \dfrac{m\lambda\ D}{d}$

for the first maxima, m = 1

 $d = \dfrac{1\times \lambda\ D}{y}$

 $d = \dfrac{1\times 550 \times 10^{-9}\times 1.5}{0.016}$

       d = 5.2 x 10⁻⁶ m

       d = 52 μm

hence, the width of her slits is equal to d = 52 μm