Question

A load of $10kN$ is supported from a pulley, which in turn is supported by a rope of cross-sectional area ${10}^{3}m{m}^2$ and modulus of elasticity ${10}^{3}Nm{m}^{-2}$ as shown in the figure. Neglecting friction at the pulley, then downward deflection of the load (in nm) is

• A. $3.75$
• B. $4.25$
• C. $2.75$
• D. $4.00$

Answer 1

The correct option is A $3.75$

$\begin{array}{cc}2T& =10kN\\ T& =5kN\\ {10}^3\times \frac{\Delta l_1}{6\times 100}& =\frac{5\times {10}^3}{{10}^3}mm\\ \Delta l_1=& 3and\Delta l_2=4.5mm\\ \Delta l=\frac{3+4.5}{2}=3.75mm& \end{array}$

Correct option is $\left(A\right)$