Question

Two light beams of intensities in the ratio of 9 : 4 are allowed to interfere. The ratio of the intensity of maxima and minima will be:

• A. 2 : 3
• B. 16 : 81
• C. 25 : 169
• D. 25 : 1

Answer 1

Answer: (D)

25 : 1

Answer 2

$\frac{I_{max}}{I_{min}} = \bigg(\frac{\sqrt{I_1}+\sqrt{I_2}}{\sqrt{I_2}-\sqrt{I_2}}\bigg)^2 = \bigg(\frac{5}{1}\bigg)^2$

= $\frac{25}{1}$