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By what percentage the impedance in an A...

By what percentage the impedance in an `AC` series circuit should be increased so that the power factor changes from `(1//2)` to `(1//4)` (when `R` is constant)?

A

`200%`

B

`100%`

C

`50%`

D

`400%`

Text Solution

Verified by Experts

The correct Answer is:
B
`cosphi=R/z`
`%` change =`(z'-z)/zxx100=100%`
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