Two monochromatic beams of intensities I and 4I respectively are superposed to form a steady interference…

Two monochromatic beams of intensities I and 4I respectively are superposed to form a steady interference pattern. The maximum and minimum intensities in the pattern are
  1. $4 \mathrm{I}$ and $\mathrm{I}$
  2. 9I and $3 \mathrm{I}$
  3. $5 \mathrm{I}$ and $3 \mathrm{I}$
  4. 9I and I

Solution

$\begin{aligned} & I_{\max }=I+4 I+2 \sqrt{(I)(4 I)}=9 I \\ & I_{\min }=I+4 I-2 \sqrt{(I)(4 I)}=I\end{aligned}$

Asked in: MHT CET 2021 (24 Sep Shift 2)

Practice more Wave Optics questions on Aicharya