Question

Two coherent sources produce waves of different intensities which interfere. After interference, the ratio of the maximum intensity to the minimum intensity is $16$. The intensity of the waves are in the ratio:

• A. 4:01
• B. 25:09:00
• C. 16:09
• D. 5:03

Answer 1

Answer: (B)

25:09:00

Answer 2

$\frac{I_{\max}}{I_{\min}} = 16$ $\Rightarrow \frac{A_{\max }}{A_{\min }} = 4$ $\Rightarrow \frac{A_{1} + A_{2}}{A_{1} - A_{2}} = \frac{4}{1}$ Using componendo & dividendo. $\frac{A_{1} }{A_{2}} = \frac{5}{3} \Rightarrow \frac{I_{1}}{I_{2}} = \left(\frac{5}{3}\right)^{2} = \frac{25}{9}$