Question

a piece of wire having a resistance R is cut into four equal parts . 1) how will the resistance of each part of the wire compare with the original resistance? 2) if the five parts of the wire are placed in parallel, how will the resistance of the combination compare with the resistance of the original wire? what will be ratio of resistance in series to that of parallel?

Answer 1

Answer:

1) r'=r/5

2) r"=r/25

3) r'/r"=25

Explanation:

using the relation r= rho L/A

if we divide its length into 5 parts each part will have resistance r/5

if the 5 parts(equal.resistance) are. place in parallel fashion then r'=r/5 ÷ 5 =r/25

if we. had connected in series then r"=5×r/5 = r

so ratio is 25:1