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An electric bulb illuminates a plane sur...

An electric bulb illuminates a plane surface. The intensity of illumination on the surface at a point 2 m away from the bulb is `5 xx 10^(-4)` phot `("lumen"//cm^(2))`. The line joining the bulb to the point makes an angle of `60^(@)` with the normal to the surface. The intensity of the bulb in candela is

A

`40 sqrt(3)`

B

40

C

20

D

`40 xx 10^(-4)`

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The correct Answer is:
b
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