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A point source of light moves ijn a stra...

A point source of light moves ijn a straight line paralel to a plane table. Consider a small portion of the table directly below the line of movement of the source. The illuminance at this portion varies with its distasnce r from the source as

A

`Iprop1/r`

B

`Iprop1/r^2`

C

`Iprop1/r^3`

D

`Iprop1/r^4`

Text Solution

Verified by Experts

The correct Answer is:
C
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