A conducting wire of length |SIMPLE HARMONIC MOTION |JEEMAIN

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JEE MAIN 2021

16-03-2021 S1

Question

A conducting wire of length 'l', area of cross-section A and electric resistivity $\rho$ is connected between the terminals of a battery. A potential difference V is developed between its ends, causing an electric current. If the length of the wire of the same material is doubled and the area of cross-section is halved, the resultant current would be :

Select the correct option:

A

$\frac{1}{4} \frac{\mathrm{VA}}{\rho l}$

B

$\frac{3}{4} \frac{\mathrm{VA}}{\rho l}$

C

$\frac{1}{4} \frac{\rho l}{V A}$

D

$4 \frac{\mathrm{VA}}{\rho l}$

✓ Correct! Well done.

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Solution

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