Question

If the length of a cylinder on heating increases by $2\%$, the area of its base will increase by

• A. $0.5\%$
• B. $2\%$
• C. $1\%$
• D. $4\%$

Answer 1

Answer: (D)

$\frac{\Delta A}{A}=2\cdot \frac{\Delta L}{L}$
$\Rightarrow \frac{\Delta A}{A}=2\times 2=4\%.$