Question

The coefficient of superficial expansion of s solid is $2\times {10}^{-5}{/}^{o}C$. Its coefficient of linear expansion is

• A. $4\times {10}^{-5}{/}^{o}C$
• B. $3\times {10}^{-5}{/}^{o}C$
• C. $2\times {10}^{-5}{/}^{o}C$
• D. $1\times {10}^{-5}{/}^{o}C$

Answer 1

The correct option is A $4\times {10}^{-5}{/}^{o}C$

Coefficient of given,

Superficial expansion $\beta =20\times {10}^{-5}{/}^{0}C$

We know that,

$6\alpha =3\beta =2\gamma$

Where $\alpha$ is linear expansion coefficient.

$\begin{array}{c}\therefore 6\times 2\times {10}^{-5}=3\beta \\ \Rightarrow \beta =2\times 2\times {10}^{-5}\\ =4\times {10}^{-5}{/}^{0}C\end{array}$

Hence,

Option $A$ is correct.