Question

A steel plate of face area $1{cm}^2$ and thickness $4cm$ is fixed rigidly at the lower surface. A tangential force $F=10kN$ is applied on the upper surface as shown in the figure. The lateral displacement $x$ of upper surface w.r.t the lower surface is (Molus of rigidity for steel is $8\times {10}^{11}N/m^2$)

• A. $5\times {10}^{-6}m$
• B. $5\times {10}^{6}m$
• C. $2.5\times {10}^{-3}m$
• D. $2.5\times {10}^{-4}m$

Answer 1

The correct option is A $5\times {10}^{-6}m$

$\begin{array}{c}\eta =\frac{F\times L}{A\times \Delta L}\\ \Delta L=\frac{F\times L}{A\times \eta }\\ \Delta L=\frac{{10}^4\times 4\times {10}^{-2}}{{10}^{-4}\times 8\times {10}^{11}}=0.5\times {10}^{-5}=5\times {10}^{-6}m\end{array}$

Hence,

option $\left(A\right)$ is correct answer.