`lambda_(1)` and `lambda_(2)` are used to illuminated the slits. `beta_(1)` and `beta_(2)` are the corresponding fringe widths. The wavelength `lambda_(1)` can produce photoelectric effect when incident on a metal But the wavelength `lambda_(2)` cannot produce photoelectric effect. The correct relation between `beta_(1)` and `beta_(2)` is

Options

A. `beta_(1) lt beta_(2)`
B. `beta_(1)=beta_(2)`
C. `beta_(1) gt beta_(2)`
D. `beta_(1) ne beta_(2)`

Answer

A

Explanation

Fringe width `beta prop lambda` As given that `lambda_(1)` wavelength photo electric effect `lamnda_(1) lt lambda_(2)`
Hence, `beta_(1) lt beta_(2)`