Question

A metallic bar is heated from 0⁰C to 100⁰C. The coefficient of linear expansion is 10^–5 K^–1 . What will be the percentage increase in length ?

• A. (a) 0.01 %
• A. (b) 0.1 %
• A. (c) 1 %
• A. (d) 10 %

Answer 1

(b)

$\frac{\Delta\mathcal{l}}{\mathcal{l}}$ = aDT = 10^–5 × 100 = 10^–3

$\frac{\Delta\mathcal{l}}{\mathcal{l}}$ × 100% = 10^–3 × 100 = 10^–1 = 0.1%