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An intensity of illumination of 4 flux i...

An intensity of illumination of 4 flux is required at a distance of 5m from an electric lamp. What must be the luminous intensity of the lamp?

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Knowledge Check

  • The maximum illumination on a screen at a distance of 2 m from a lamp is 25 lux . The value of total luminous flux emitted by the lamp is

    A
    1256 lumen
    B
    1600 lumen
    C
    100 candela
    D
    400 lumen
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