Masses of 3 wires of same metal are in the ratio 1 : 2 : 3 and their lengths are in the ratio 3 : 2 : 1. The electrical resistances are in ratio

Options

A. `1:1:1`
B. `1:2:3`
C. `9:4:1`
D. `27: 6:1`

Answer

4

Explanation

`rho` is same so `Rprop(l)/(A)`
Now m d `rArr m=Ald`
`Aprop(m)/(l) rArrR prop(l^(2))/(m)`
`R_(1):R_(2):R_(3)=(9)/(1):(4)/(2):(1)/(3)=27:6:1`