In a Young's double slit experiment an electron beam is used to obtain interference pattern. If the speed of electron decreases then

Options

A. distance between two consecutive fringes remains the same
B. distance between two consecutive fringes decreases
C. distance between two consecutive fringes increases
D. None of these.

Answer

C

Explanation

Fringe width, `beta = (lambda D)/(d)`, Also, `lambda=(h)/(mv)`
Here h is planck's constant. This wavelength is inversely proportional to the velocity. Hence, the fringe width increases with decrease in electron speed.