The upper end of a wire of radius $4\, mm$ and length $100\, cm$ is clamped and its other end is twisted through an angle of $30^\circ$. The angle of shear is ..... $^\circ$.

$A$ square lead slab of side $50\, cm$ and thickness $10\, cm$ is subject to a shearing force (on its narrow face) of $9.0 \times 10^{4} \, N$. The lower edge is riveted to the floor. How much will the upper edge be displaced? (Given: Shear modulus of lead $G = 5.6 \times 10^{9} \, N/m^2$)

The upper end of a wire of radius $4 \, mm$ and length $100 \, cm$ is clamped and its other end is twisted through an angle of $60^o$. The angle of shear is .......... $^o$.

As shown in the figure,forces of $10^5\,N$ each are applied in opposite directions on the upper and lower faces of a cube of side $10\,cm$,shifting the upper face parallel to itself by $0.5\,cm$. If the side of another cube of the same material is $20\,cm$,then under similar conditions as above,the displacement will be ......... $cm$.

$A$ square aluminium (shear modulus is $25 \times 10^{9} \, N m^{-2}$) slab of side $60 \, cm$ and thickness $15 \, cm$ is subjected to a shearing force (on its narrow face) of $18.0 \times 10^{4} \, N$. The lower edge is riveted to the floor. The displacement of the upper edge is $....... \mu m$.

$A$ rectangular metallic block of dimensions $40 \text{ mm} \times 20 \text{ mm}$ when pulled with a tension of $50 \text{ kN}$ undergoes only elastic deformation. The strain in the block is (The shear modulus of the material of the block is $40 \times 10^9 \text{ Nm}^{-2}$)