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Question
The electric field intensity produced by the radiations coming from 100 W bulb at a 3 m distance is E. The electric field intensity produced by the radiations coming from 50 W bulb at the same distance is ______.
Options
`E/2`
2E
`E/sqrt(2)`
`sqrt(2)E`
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Solution
The electric field intensity produced by the radiations coming from 100 W bulb at a 3 m distance is E. The electric field intensity produced by the radiations coming from 50 W bulb at the same distance is `underline(E/sqrt(2)`.
Explanation:
`E_0 oo sqrt(P_(av))`
`(E_0)_1/(E_0)_2 = sqrt(((P_(av))_1)/(P_(av))_2) = sqrt((100 W)/(50 W)) = sqrt(2)/1`
∴ `(E_0)_2 = (E_0)_1/sqrt(2)`
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