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In a grease spot photometer light from a...

In a grease spot photometer light from a lamp with dirty chimney is exactly balanced by a point source distance 10 cm from the grease spot. On clearing the chimney, the point source is moved 2 cm to obtain balance again. The percentage of light absorbed by dirty chimney is nearly

A

`56%`

B

`44%`

C

`36%`

D

`64%`

Text Solution

Verified by Experts

The correct Answer is:
c
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