Question

Two wires A and B are made of same material same length have radii as R , 2R .The ratio of

resistance of wire A to that of B is

A) 1:2 B) 2:1 C) 4:1 D) 1:4​

Answer 1

Explanation:

Resistance of a wire depends inversely on square of radius of the wire's area of

cross section. Hence, the ratio of resistances of Wire AtoB is-

Ra/Rb= (2R/R)^2 = 4:1 (c)