The camera lens has an aperture of f and the exposure time is 1/60 s. What will be the new exposure time if the aperture become 1.4 f?

The camera lens has an aperture of f and the exposure time is 1/60 s.

1.	The camera lens has an aperture of f and the exposure time is 1/60 s. What will be the new exposure time if the aperture become 1.4 f?
Answer» `(1)/(42)s` `(1)/(56)s` `(1)/(72)s` `(1)/(31)s` Solution :TIME of EXPOSURE `prop (f - "number")^(2)` `therefore(t)/(((1)/(60)))=((1.4)/(1))^(2)rArrt=(1.4xx1.4)/(60)APPROX(1)/(31)s`

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The camera lens has an aperture of f and the exposure time is 1/60 s. What will be the new exposure time if the aperture become 1.4 f?

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