Two wires of the same material (Young's modulus $Y$ ) and same length $L$ but radii $R$ and $2R$ respectively are joined end to end and a weight $W$ is suspended from the combination as shown in the figure. The elastic potential energy in the system is
$\frac{{3{W^2}L}}{{4\pi {R^2}Y}}$
$\frac{{3{W^2}L}}{{8\pi {R^2}Y}}$
$\frac{{5{W^2}L}}{{8\pi {R^2}Y}}$
$\frac{{{W^2}L}}{{\pi {R^2}Y}}$
When strain is produced in a body within elastic limit, its internal energy
If a spring extends by $x$ on loading, then the energy stored by the spring is (if $T$ is tension in the spring and $k$ is spring constant)
Wires $A$ and $B$ are made from the same material. $A$ has twice the diameter and three times the length of $B.$ If the elastic limits are not reached, when each is stretched by the same tension, the ratio of energy stored in $A$ to that in $B$ is
The elastic energy stored in a wire of Young's modulus $Y$ is
If $x$ longitudinal strain is produced in a wire of Young's modulus $y,$ then energy stored in the material of the wire per unit volume is