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A battery operated torch is adjusted to ...

A battery operated torch is adjusted to send and almost parallel beam of light. It produces an illuminance of 40 lux when the light falls on a wall 2 m away. The illuminance produced when it falls on a wail 4 m away is close to

A

40 lux

B

20 lux

C

10 lux

D

5 lux

Text Solution

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The correct Answer is:
A
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