Question

If a 4 ohm resistance wire is doubled by folding it the new resistance will be how much

Answer 1

When the wire is doubled the length will be halved and area will be double or twice 

R = PL/A 

R1 = P(L/2) / 2A Where R1 is the new resistance 

So R1/R = {P(L/2) / 2A} / {PL/A} 

When we solve this we get  R1/R = ¼ 

=> R1 = R/4 = 4/4 = 1 OHM