How can we change a camera from F/4 to F/5.6? | vedclass

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(D) The $F$-number of a camera is defined as the ratio of the focal length $(f)$ to the diameter of the aperture $(D)$: $F = \frac{f}{D}$.For an $F/4$

Vedclass · Accepted Answer

Increase the aperture to $\frac{1}{\sqrt{2}}$ times keeping the focal distance constant.

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(D) The $F$-number of a camera is defined as the ratio of the focal length $(f)$ to the diameter of the aperture $(D)$: $F = \frac{f}{D}$.For an $F/4$ setting,the $F$-number is $4$,so $4 = \frac{f}{D_1}$,which implies $D_1 = \frac{f}{4}$.For an $F/5.6$ setting,the $F$-number is $5.6$,so $5.6 = \frac{f}{D_2}$,which implies $D_2 = \frac{f}{5.6}$.To find the change in aperture,we take the ratio: $\frac{D_2}{D_1} = \frac{f/5.6}{f/4} = \frac{4}{5.6}$.Since $5.6 \approx 4 	imes \sqrt{2}$,we have $\frac{D_2}{D_1} = \frac{4}{4 	imes \sqrt{2}} = \frac{1}{\sqrt{2}}$.Therefore,the aperture $D_2$ must be $\frac{1}{\sqrt{2}}$ times the original aperture $D_1$.

How can we change a camera from $F/4$ to $F/5.6$?

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