Question

One of the mirrors of a Michelson interferometer is moved, and a shift of 140 fringes in the output pattern occurs. If the device is illuminated with 500 nm light, how far was the mirror moved

Answer 1

0.035mm

Step-by-step explanation:

Given; wavelength λ = 500nm = 0.0005mm, Number of fringe m = 140, d = ?

In Michelson interferometer, distance moved by the mirror is given by,

d = m*λ/2

d = 140*0.0005/2 = 0.035mm