Question

If the rms current in a 50 Hz ac circuit is 5 A, the value of the current `1//300` second after its value becomes zero is
A. `5sqrt(2)`A
B. `5sqrt(3//2)` A
C. `5//6` A
D. `5//sqrt(2)` A

Answer 1

Correct Answer - B
Given, `v=50Hz, I_(rms)=5A`
`t=1/300s`
We have to find I(t)
`I_(0)= "Peak value"=sqrt(2), I_(rms)=sqrt(2) xx5`
`=5sqrt(2)` A
`I=I_(0)sinomegat=5sqrt(2)sin2pivt=5sqrt(2)sin 2pi xx 50 xx 1/300`
`=5sqrt(2)sin pi/3=5sqrt(2) xx sqrt(3)/2 = 5sqrt(3//2)` A