A steel rod of length $\ell$, cross sectional area $A$, young's modulus of elasticity $Y$, and thermal coefficient of linear expansion $'a'$ is heated so that its temperature increases by $t\,^oC$. Work that can be done by rod on heating will be
$(YA\, \alpha\, t)\times(\ell\, \alpha\, t)$
$\frac{1}{2}\left( {YA\,\alpha \,t} \right) \times \left( {\ell \,\alpha \,t} \right)$
$\frac{1}{2}\left( {YA\,\alpha \,t} \right) \times \left( {1/2} \right)\left( {\ell \,\alpha \,t} \right)$
$2(YA\, \alpha\, t)\,(\ell\, \alpha\, t)$
Why do spring balances show wrong readings of weight after they have been used for a long time ?
A metallic rod of length $I$ and cross-sectional area $A$ is made of a material of Young's modulus $Y$. If the rod is elongated by an amount $y$, then the work done is proportional to ......
The elastic potential energy stored in a steel wire of length $20\,m$ stretched through $2 \,m$ is $80\,J$. The cross sectional area of the wire is $.........\,mm ^2$ (Given, $y =2.0 \times 10^{11}\,Nm ^{-2}$ )
The elastic behaviour of material for linear streass and linear strain, is shown in the figure. The energy density for a linear strain of $5 \times 10^{-4}$ is $\dots \; kJ / m ^{3}$. Assume that material is elastic upto the linear strain of $5 \times 10^{-4}$.
On stretching a wire, the elastic energy stored per unit volume is