The exposure time of a camera lens at the `(f)/(2.8)` setting is `(1)/(200) ` second. The correct time of exposure at `(f)/(5.6)` isA. `0.4 sec`B. `0.02 sec`C. `0.002 sec`D. `0.04 sec`

The exposure time of a camera lens at the `(f)/(2.8)` setting is `(1)/

1.	The exposure time of a camera lens at the `(f)/(2.8)` setting is `(1)/(200) ` second. The correct time of exposure at `(f)/(5.6)` isA. `0.4 sec`B. `0.02 sec`C. `0.002 sec`D. `0.04 sec`
Answer» Correct Answer - B Time of exposure `prop (f.n umber)^(2)` `implies(t_(2))/(f_(1))=((5.6)/(2.8))^(2)=4` `t_(2)=4t_(1)=4xx(1)/(200)=(1)/(50)sec=0.02 sec.`

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The exposure time of a camera lens at the `(f)/(2.8)` setting is `(1)/(200) ` second. The correct time of exposure at `(f)/(5.6)` isA. `0.4 sec`B. `0.02 sec`C. `0.002 sec`D. `0.04 sec`

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