A battery-operated torch is adjusted to send an 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 wall 4 m away is close to

A battery-operated torch is adjusted to send an almost parallel beam of light. Thus, illuminance produced will remain same with increase in distance. The value of illuminance is 40 mux only.


So, option A is correct.

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