Question

Michelson’s interferometer, if the moveable mirror is displaced through a distance of 0.05 mm, 200 fringes are observed to be shifted. The wavelength of the light used is​

Answer 1

Answer:

The Michelson interferometer (invented by the American physicist Albert A. Michelson, 1852–1931) is a precision instrument that produces interference fringes by splitting a light beam into two parts and then recombining them after they have traveled different optical paths. (Figure) depicts the interferometer and the path of a light beam from a single point on the extended source S, which is a ground-glass plate that diffuses the light from a monochromatic lamp of wavelength {\lambda }_{0}. The beam strikes the half-silvered mirror M, where half of it is reflected to the side and half passes through the mirror. The reflected light travels to the movable plane mirror {\text{M}}_{1}, where it is reflected back through M to the observer. The transmitted half of the original beam is reflected back by the stationary mirror {\text{M}}_{2} and then toward the observer by M.

(a) The Michelson interferometer. The extended light source is a ground-glass plate that diffuses the light from a laser. (b) A planar view of the interferometer.