A gas in an airtight container is heated from $25°C$ to $90°C$. The density of the gas will
Increase slightly
Increase considerably
Remain the same
Decrease slightly
Why the density is changed of solid substances by increase in temperature ?
What is areal expansion ? Give definition and unit of coefficient of areal expansion.
Coefficient of linear expansion of a vessel completely filled with $Hg$ is $1 \times 10^{-5} /{ }^{\circ} C$. If there is no overflow of $Hg$ on heating the vessel, then coefficient of cubical expansion of $Hg$ is ......
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} ) $
If the length of a cylinder on heating increases by $2\%$, the area of its base will increase by ....... $\%$