In the adjacent diagram, CP represents a wavefront and AO & BP, the corresponding two rays. What would be the condition on θ for constructive interference at P between the ray BP and reflected ray OP?
(1) cosθ = 3λ/2d
(2) cosθ = λ/4d
(3) secθ – cosθ = λ/d
(4) secθ – cosθ = 4λ/d
A beam with wavelength λ falls on a stack of partially reflecting planes with separation d. The angle θ that the beam should make with the planes so that the beams reflected from successive planes may interfere constructively is (where n =1, 2, ……)
(1)
(2)
(3)
(4)
Which of the following property of light is a sure proof of wave nature of light?
1. Interference
2. Diffraction
3. Photoelectric Effect
4. Both (1) & (2)