Q 11-08-009NEETJEE MainMedium
A metal cube of side $10$ cm has its bottom face fixed. A tangential force of $10^4$ N is applied to its top face. The shear modulus of the metal is $2.5 \times 10^{10}$ N m$^{-2}$. The top face moves sideways by
Answer: (A) $4\ \mu$m
Shear stress $= \dfrac{F}{A} = \dfrac{10^4}{0.01} = 10^6$ N m$^{-2}$.
Shear strain $= \dfrac{10^6}{2.5 \times 10^{10}} = 4 \times 10^{-5}$.
Displacement $= \text{strain} \times \text{side} = 4 \times 10^{-5} \times 0.1 = 4 \times 10^{-6}$ m $= 4\ \mu$m.
Solution by Sreeraj P, M.Sc Physics