Question

A wire of given material having length l and area of cross-section A has a resistance of 4ꭥ. What would be the resistance of another wire of the same material having l/2 and area of cross-section 2A?

Answer 1

Answer:

Given;

L=l,

A=a,

R=4 ohm

Now, R=p*L/A

4=p*L/A.......(i)

Now,

L1=l/2

A1=2a

R'=p*L1/A1

R'=p*l/2/2a

R'=p*2*l/2*a

R'=1*p*l/a......(ii)

R'=1*4............(putting value of i in ii equation R=p*l/a)

R'=4 ohm

Hence, Resistance of another wire is 4 ohm

I hope it is helpful for you