Question

A metallic bar is heated from $0^{\circ} C$ to $100^{\circ}C $. The coeficient of linear expansion is $10^{-5} \, K^{-1}$. What will be the percentage increase in length?

• A. 0.01 %
• B. 0.1 %
• C. 1 %
• D. 10 %

Answer 1

Answer: (B)

$\frac{\Delta l}{l} = \alpha \Delta T = 10^{-5} \times100 = 10^{-3}$
$ \frac{\Delta l}{l} \times100\% = 10^{-3} \times100 $
$ = 10^{-1} = 0.1 \%$