$A$ metallic tape gives the correct value at $25^{\circ} C$. $A$ piece of wood is being measured by this metallic tape at $10^{\circ} C$. If the reading is $30 \, cm$ on the tape, the real length of the wooden piece must be .......... $cm$.

What is the change in volume of an iron sphere of volume $500 \,cm^3$, when it is heated from $0^{\circ} C$ to $100^{\circ} C$ (in $\,cm^3$)? (Given: $\alpha_{\text{Iron}} = 12 \times 10^{-6} /^{\circ} C$)

The volume of a metal block increases by $0.225 \%$ when its temperature is increased by $30^{\circ} C$. Hence,the coefficient of linear expansion of the material of the metal block is

What happens during the thermal expansion of a material when it is heated?

$A$ glass flask contains some mercury at room temperature. It is found that at different temperatures the volume of air inside the flask remains the same. If the volume of mercury in the flask is $300 \, cm^3$,then the volume of the flask is ........ $cm^3$. (Given that the coefficient of volume expansion of mercury is $\gamma_{Hg} = 1.8 \times 10^{-4} (^{\circ}C)^{-1}$ and the coefficient of linear expansion of glass is $\alpha_{glass} = 9 \times 10^{-6} (^{\circ}C)^{-1}$)

What must be the lengths of steel and copper rods at $0^o C$ for the difference in their lengths to be $10\,cm$ at any common temperature? $(\alpha_{steel}=1.2 \times 10^{-5} \;^o C^{-1})$ and $(\alpha_{copper} = 1.8 \times 10^{-5} \;^o C^{-1})$