Question

In a double-slit experiment, two beams of coherent light traveling different paths arrive on a screen some distance away. What is the path difference between the two waves corresponding to the third bright band out from the central bright band?

Answer 1

Destructive interference occurs when path difference = ½-integer multiple of the wavelength i.e. Minima in diffraction pattern given by, = ! + # λ = !1 + # λ = 3λ/2 m