Light from a point source falls on a small area placed perpendicular to the incident light. If the area is rotated about the incident light by an angle of `60^(@)` , by what fraction will the illuminance changeA. It will be doubledB. It will be halvedC. It will not changeD. It will become one-fourth

Light from a point source falls on a small area placed perpendicular t

1.	Light from a point source falls on a small area placed perpendicular to the incident light. If the area is rotated about the incident light by an angle of `60^(@)` , by what fraction will the illuminance changeA. It will be doubledB. It will be halvedC. It will not changeD. It will become one-fourth
Answer» Correct Answer - c

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