MCQ
Two monochromatic light beams have intensities in the ratio 1:9. An interference pattern is obtained by these beams. The ratio of the intensities of maximum to minimum is
- A$8: 1$
- B$9: 1$
- C$3: 1$
- D$4: 1$
✓
Answer
D. $4: 1$
$\frac{I_{\max }}{I_{\min }}=\frac{\left(\sqrt{\mathrm{I}_{1}}+\sqrt{\mathrm{I}_{2}}\right)^{2}}{\left(\sqrt{\mathrm{I}_{1}}-\sqrt{\mathrm{I}_{2}}\right)^{2}} \Rightarrow \frac{(4)^{2}}{(2)^{2}} \Rightarrow \frac{16}{4}=4$
$\frac{I_{\max }}{I_{\min }}=\frac{\left(\sqrt{\mathrm{I}_{1}}+\sqrt{\mathrm{I}_{2}}\right)^{2}}{\left(\sqrt{\mathrm{I}_{1}}-\sqrt{\mathrm{I}_{2}}\right)^{2}} \Rightarrow \frac{(4)^{2}}{(2)^{2}} \Rightarrow \frac{16}{4}=4$
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