Question 311: Wave Optics

Question

The intensity of light coming from one of the slits in Young's double slit experiment is double the intensity from the other slit. The ratio of the maximum intensity to the minimum intensity in the interference fringe pattern observed is

Accepted Answer

Two coherent sources of intensities $\mathrm{I}_1$ and $\mathrm{I}_2$ produce,
maximum intensity, $\mathrm{I}_{	ext {max }}=\left(\sqrt{I_1}+\sqrt{I_2}ight)^2$ and
minimum intensity, $I_{	ext {min }}=\left(\sqrt{I_1}-\sqrt{I_2}ight)^2$ in an interference pattern.
$$\begin{aligned}
& \frac{I_{\max }}{I_{\min }}=\frac{\left(\sqrt{I_1}+\sqrt{I_2}ight)^2}{\left(\sqrt{I_1}-\sqrt{I_2}ight)^2}=\frac{I_1+I_2+2 \sqrt{I_{I_2}}}{I_1+I_2-2 \sqrt{I_1 I_2}}
\end{aligned}$$
Given $\mathrm{I}_1=2 \mathrm{I}_2$
$$\begin{aligned}
	herefore \quad & \frac{\mathrm{I}_{	ext {max }}}{\mathrm{I}_{\min }}=\frac{3 \mathrm{I}_2+2 \sqrt{2} \mathrm{I}_2}{3 \mathrm{I}_2-2 \sqrt{2} \mathrm{I}_2}=\frac{3+2 \sqrt{2}}{3-2 \sqrt{2}}=34
\end{aligned}$$

Answer

$9: 1$

Answer

$34: 1$

Answer

$4: 1$

Answer

$16: 1$

Wave Optics

The intensity of light coming from one of the slits in Young's double slit experiment is double the intensity from the other slit. The ratio of the maximum intensity to the minimum intensity in the interference fringe pattern observed is

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