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An ac voltage is represented by E=220...

An ac voltage is represented by
`E=220 sqrt(2) cos (50 pi) t`
How many times will the current become zero in 1 s?

A

(A) 50 times

B

(B) 100 times

C

(C) 30 times

D

(D) 25 times

Text Solution

Verified by Experts

The correct Answer is:
A

`E=(E_0) cos omega t`
`:. Omega =50 pi`
`2 pi f = 50 pi implies f=25 Hz`
In one cycle ac current becomes zero twice.
therefore, 50 times the current becomes zero in 1 s.
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