Question

The breaking force of wire is `10^(4)`N and radius is `1xx10^(-3)`m. If the radius is `2xx10^(-3)`m, then the breaking force will be
A. `4xx10^(4)N`
B. `40xx10^(4)N`
C. `0.04xx10^(4)N`
D. `0.4xx10^(4)N`

Answer 1

Correct Answer - A
`(F_(2))/(F_(1))=((r_(2))/(r_(1)))^(2)=((2xx10^(-3))/(1xx10^(-3)))^(2)=4`
`F_(2)=4F_(1)`
`=4 xx 10^(4)N`.