Question

Light of wavelength `600 nm` is incident normally on a slit of width `3 mm`. Calculate linear width of central maximum on a screen kept `3 m` away from the slit.

Answer 1

Correct Answer - `1.2 mm`
Here, `lambda = 600 nm = 6 xx 10^(-7)m`,
`a = 3 mm = 3 xx 10^(-3)m`
`D = 3 m , (2x) = ?`
`2x = (2 lambda D)/(a) = (2 xx 6 xx 10^(-7) xx 3)/(3 xx 10^(-3))`
`= 12 xx 10^(-4)m = 1.2 mm`