$A$ cube has side length $5$ cm and modulus of rigidity $10^5$ $N$/m$^2$. The displacement produced by a force of $10$ $N$ in the upper face of cube is . . . . . . mm.

The upper end of a wire $1\,m$ long and $4\,mm$ radius is clamped. The lower end is twisted by an angle of $30^\circ$. The angle of shear is ...... $^\circ$.

Two slabs with square cross-sections of different materials $(1, 2)$ have equal sides $(l)$ and thicknesses $d_1$ and $d_2$ such that $d_2 = 2d_1$ and $l > d_2$. Considering the lower edges of these slabs are fixed to the floor,we apply equal shearing force on the narrow faces. The angle of deformation is $\theta_2 = 2\theta_1$. If the shear modulus of material $1$ is $4 \times 10^9 \ N/m^2$,then the shear modulus of material $2$ is $x \times 10^9 \ N/m^2$,where the value of $x$ is . . . . . . .

Shear modulus is zero for

Assume that a block of very low shear modulus is fixed on an inclined plane as shown. Due to elastic forces,it will deform. What will be the shape of the block?

The strain energy stored in a body of volume $V$ due to shear strain $\phi$ is (shear modulus is $\eta$ ).