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If the current flowing through a coil is...

If the current flowing through a coil is reduced by 50% then the energy in the coil

A

will not increased

B

will not change

C

will be decreased by 20%

D

will be decreased by 75%

Text Solution

Verified by Experts

The correct Answer is:
D
`(E_2)/(E_1)= (1/2L((I)/(2))^(2))/(1/2LI^(2)) =1/4`
`E_(2) = 1/4 E_(1) :. E_(1)-E_(2) = 3/4 E_(1)`.
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