Question

To break a wire, a force of ${10}^{6}N/m^2$ is required. If the density of the material is $3\times {10}^{3}kg/m^3$, then the length of the wire which will break by its own weight will be

• A. $34m$
• B. $30m$
• C. $300m$
• D. $3m$

Answer 1

The correct option is A $34m$

Force per unit area on the wire due to its own weight is given by $\rho gl$
$\rho gl=S$
$l=\frac{S}{\rho g}=\frac{{10}^6}{3\times {10}^3\times 9.81}=33.979m$
Option A.