Question

A wire of length = l and resistance = R , if it streched such that its length becomes 3 times more of its initial one. Find the ratio of initial resistance to the newly obtained resistance.​

Answer 1

1:3 is the required answer

Explanation:

According to the Question

It is given that ,

Length of wire = l

Resistance ,R

Resistance in 1st case :-

R = ρl/A

where

R denote Resistance

ρ denote electrical resistivity

l denote length of wire

A denote Area of cross section .

→ R = ρl/A ------------(i)

Again in second case the wire is stretched such that it's length become 3 times as initial was .

New length of Wire = 3l

Resistance in 2nd case :-

→ R = ρ3l/A -----------(ii)

From equation (i) & (ii) we get

→ ρl/A = ρ3l/A

→ l = 3l

→ 1 = 3

Hence, the ratio of initial resistance to the newly obtained resistance will be 1:3 .

or

Given:-

A wire of length =I and resistance =R , if its stretched such that its length become 3 times more than its initial one.

To find :-

Find the ratio of initial resistance to the newly obtained resistance.

Explanation :-

Refer the attachment for more information.

We get the answer as the ratio of 1:3

both the answers are correct

Answer 2

Step-by-step explanation:

$answer \: in \: attachment \:$

Hope it helps !