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A wire when connected to 220 V mains sup...

A wire when connected to 220 V mains supply has power dissipation `P_(1)`. Now the wire is cut into two equal pieces which are connected in parallel to the same supply. Power dissipation in this case is `P_(2)`. Then `P_(2) : P_(1)` is

A

`1`

B

`4`

C

`2`

D

`3`

Text Solution

Verified by Experts

The correct Answer is:
B
`P = V^(2)// R`. `R` is reduced by a factor of `4` . So `P` is increased by a factor `4`.
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