Question

A wire whose cross-sectional area is $4m{m}^2$ is stretched by $0.1mm$ by a certain load. If a similar wire of double the area of cross-section is under the same load, then the elongation would be

• A. $0.5mm$
• B. $0.05mm$
• C. $0.005mm$
• D. $5mm$

Answer 1

The correct option is B $0.05mm$

$0.05mm$

Formula,

$y=\frac{Fl}{Ae}$

$\Rightarrow e\propto \frac{1}{A}$

$\frac{e_2}{0.1}=\frac{4}{8}=\frac{1}{2}$

$\therefore e_2=0.05mm$