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A photographic plate placed at a distanc...

A photographic plate placed at a distance of 5 cm from a weak point source is exposed for 3 s. If the plate is kept at a distance of 10 cm from the source, the time needed for the same exposure is

A

3s

B

12s

C

24s

D

48s

Text Solution

Verified by Experts

The correct Answer is:
B
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