$A$ thin copper wire of length $l$ meters is heated by $10^{\circ}C$,resulting in a $2\%$ increase in its length. If a square copper sheet of side $l$ meters is heated by the same $10^{\circ}C$,what is the percentage change in its area?

Coefficient of linear expansion of brass and steel rods are $\alpha_1$ and $\alpha_2$. Lengths of brass and steel rods are $l_1$ and $l_2$ respectively. If $(l_2 - l_1)$ is maintained same at all temperatures,which one of the following relations holds good?

Why does the density of solid substances change with an increase in temperature?

$A$ steel scale measures the length of a copper wire as $80.0\,cm$ when both are at $20^\circ C$ (the calibration temperature for the scale). What would be the scale reading for the length of the wire when both are at $40^\circ C$ (in $,cm$)?

$A$ rod of length $10 \, m$ at $0 \, ^oC$ has a linear expansion coefficient $\alpha = (2x^2 + 1) \times 10^{-6} \, ^oC^{-1}$,where $x$ is the distance from one end of the rod. The length of the rod at $10 \, ^oC$ is: (in $, m$)

$A$ steel tape of $300 \,cm$ length is graduated at $27^{\circ} C$. The length of a steel rod measured using the tape is found to be $110 \,cm$ at $50^{\circ} C$. The actual length of the steel rod at $50^{\circ} C$ is $(\alpha_{\text{steel}} = 1.2 \times 10^{-5} \,K^{-1})$. (in $\,cm$)