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Q.
The density of a substance at $0^{\circ} C$ is $10\, g / cc$ and at $100^{\circ} C$, its density is $9.7\, g / cc$. The coefficient of linear expansion of the substance is
Coefficient of volume expansion is three times the coefficient of linear expansion.
The coefficient of volume expansion is given by
$\gamma=\frac{\Delta \rho}{\rho_1 \times \Delta T}$
where $\rho_1$ is density, $T$ is temperature.
$\gamma =\frac{\rho_1-\rho_2}{\rho_1\left(T_2-T_1\right)} $
$=\frac{10-9.7}{10(100-0)}=3 \times 10^{-4}$
Coefficient of linear expansion is
$\alpha=\frac{\gamma}{3}=\frac{3 \times 10^{-4}}{3}=10^{-4}$