Question

-
A wirre of resistance (P is stretched cal
double its orignol length (bithrice the orignal
length. calculale new resistance and
resistruity in both cases​

Answer 1

Explanation:

L be initial length of wire with resistance R and its area of cross section is A.

We know that,

RαL

and Rα

A

1

If the L length of wire is stretched to 1L length then its Area of cross section.

becomes half, i.e., =

2

A

We know that, R=

A

ρL

Where ρ is known as resistivity of an conductor.

On putting values, R=

A/2

ρ2L

R=4

A/2

ρL

Then Resistance becomes 4 times of the resistance of L length with A cross section.