Question

Two wires A and B of same length, same area of cross-section having the same Young's modulus are heated to the same range of temperature. If the coefficient of linear expansion of A is 3/2 times of that of wire B. The ratio of the forces produced in two wires will be

• A. $\frac{2}{3}$
• B. $\frac{9}{4}$
• C. $\frac{4}{9}$
• D. $\frac{3}{2}$

Answer 1

The correct option is D

$\frac{3}{2}$

$F=YA\alpha \Delta \theta$

If Y, A and $\Delta \theta$ are constant then $\frac{F_A}{F_B}=\frac{{\alpha }_A}{{\alpha }_B}=\frac{3}{2}$