Question 416: Wave Optics

Question

Two slits in Young's experiment have widths in the ratio 1 : 25. The ratio of intensity at the maxima and minima in the interference pattern,  $${{{I_{max}}} \over {{I_{min}}}}$$ is

Accepted Answer

Given, The ratio of slits width = $${1 \over {25}}$$
$$ 	herefore $$ $${{{I_1}} \over {{I_2}}} = {{25} \over 1}$$
I $$ \propto $$ A
2
$$ \Rightarrow $$ $${{{I_1}} \over {{I_2}}} = {{A_1^2} \over {A_2^2}}$$ = $${{25} \over 1}$$
$$ \Rightarrow $$ $${{{A_1}} \over {{A_2}}} = {5 \over 1}$$
$${{{A_{\max }}} \over {{A_{\min }}}} = {{{A_1} + {A_2}} \over {{A_1} - {A_2}}}$$ = $${{5 + 1} \over {5 - 1}}$$ = $${6 \over 4}$$ = $${3 \over 2}$$
$$ 	herefore $$ $${{{I_{\max }}} \over {{I_{\min }}}} = {{A_{\max }^2} \over {A_{\min }^2}}$$ = $${\left( {{3 \over 2}} ight)^2}$$ = $${9 \over 4}$$

Answer

$${{49} \over {121}}$$

Answer

$${4 \over 9}$$

Answer

$${9 \over 4}$$

Answer

$${{121} \over {49}}$$

Wave Optics

Two slits in Young's experiment have widths in the ratio 1 : 25. The ratio of intensity at the maxima and minima in the interference pattern, ${{{I_{max}}} \over {{I_{min}}}}$ is

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