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An e.m.f. E=4cos(1000t)volt is applied t...

An e.m.f. `E=4cos(1000t)`volt is applied to an `LR` circuit of inductance `3mH` and resistance `4ohm`. The amplitude of current in the circuit is

A

`8A`

B

`4A`

C

`0.8A`

D

0.4 A

Text Solution

Verified by Experts

The correct Answer is:
C
`e_(0)=4V,X_(L)=omegaL=3Omega`
`Z=sqrt(R^(2)+X_(L)^(2))=5Omega`
`I_(0)=(e_(0))/(Z)=(4)/(5)=0.8A`.
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