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When a wire is stretched and its radius ...

When a wire is stretched and its radius becomes `r//2` then its resistance will be

A

16 R

B

4 R

C

2 R

D

`R//2`

Text Solution

Verified by Experts

The correct Answer is:
A
`(R_(2))/(R_(1))=((r_(1))/(r_(2)))^(4)`
`R_(2)=(((r_(1))/(r_(1)))/(2))^(4)xxR_(1)=16.R_(1)=16R`
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