Question

Two metallic wires A and B of the sauce material are connected in parallel. Wire A has the length 'L' and radius 'r' and wire B has the length '2L' and radius '2r'. Compute the ratio of total resistance of parallel combination to the resistance of wire A.

Answer 1

Answer:

1:2.

Explanation:

R1=(rho)L/A.

R2=(rho)2L/2A.

2 and 2 cancel each other.

R2=(rho)L/A.

Hence,

R1=R2.

In parallel combination,

Total 1/R=1/R1 + 1/R2...........(1)

Since R1=R2,

R=R1/2.(Keeping value of R2=R1 in (1)).

Ratio R:R1=1:2.