Two coherent monochromatic light beams of intensities I and 4I are superimposed. The difference between maximum and minimum possible intensities in the resulting beam is x I. The value of x is .
Answer
8
Solution
I A2, the amplitudes are in the ratio 1 : 2
Imax = ( I + 2 I)2 = 9I (in phase)
Imin = (2 I - I)2 = I (opposite phase)
Imax - Imin = 8I x = 8
Answer: 8