Two different wires having lengths $L _{1}$ and $L _{2}$ and respective temperature coefficient of linear expansion $\alpha_{1}$ and $\alpha_{2},$ are joined end-to-end. Then the effective temperature coefficient of linear expansion is
$4 \frac{\alpha_{1} \alpha_{2}}{\alpha_{1}+\alpha_{2}} \frac{ L _{2} L _{1}}{\left( L _{2}+ L _{1}\right)^{2}}$
$2 \sqrt{\alpha_{1} \alpha_{2}}$
$\frac{\alpha_{1}+\alpha_{2}}{2}$
$\frac{\alpha_{1} L_{1}+\alpha_{2} L_{2}}{L_{1}+L_{2}}$
Show that the coefficient of area expansion, $(\Delta A / A) / \Delta T,$ of a rectangular sheet of the solid is twice its Iinear expansivity, $\alpha_{1}$
Obtain relation between coefficient of volume expansion $(\alpha _v)$ and coefficient of linear expansion $(\alpha _l)$.
A litre of alcohol weighs
A copper rod of $88\; \mathrm{cm}$ and an aluminum rod of unknown length have their increase in length independent of increase in temperature. The length of aluminum rod is....$cm$
$( \alpha_{Cu}=1.7 \times 10^{-5}\; \mathrm{K}^{-1}$ and $\alpha_{Al}=2.2 \times 10^{-5} \;\mathrm{K}^{-1} ) $
Water falls from a height $500m$. What is the rise in temperature of water at bottom if whole energy remains in the water ........... $^\circ \mathrm{C}$