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

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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 60o, by what fraction will the illuminance change
A.	It will be doubled
B.	It will be halved
C.	It will not change
D.	It will become one-fourth
Answer» D. It will become one-fourth

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