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If the focal length of a lens of a camer...

If the focal length of a lens of a camera is 5f and that of another is 2.5 f what is the time of exposure for the second if for the first one is 1/200s (where f is focal length /unit aperture)

A

1/200

B

1/800

C

(1/6400)

D

(1/3200)

Text Solution

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The correct Answer is:
B
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