$A$ bob of mass $10\, kg$ is attached to a wire $0.3\, m$ long. Its breaking stress is $4.8 \times 10^7\, N/m^2$. The area of cross-section of the wire is $10^{-6}\, m^2$. The maximum angular velocity with which it can be rotated in a horizontal circle is ....... $rad/sec$.

Statement $(A)$ For an ideal liquid,the bulk modulus is infinite and the shear modulus is zero.
Statement $(B)$ The volume contraction of a metal cube of bulk modulus $140 \text{ GPa}$ and side length $10 \text{ cm}$,when subjected to a hydraulic pressure of $7 \times 10^6 \text{ Pa}$,is $-0.05 \text{ m}^3$.
Statement $(C)$ $A$ spiral spring is stretched by a weight attached to it. The strain is tensile.

Which of the following materials is non-crystalline?

$A$ rod of length $1.05 \; m$ having negligible mass is supported at its ends by two wires of steel (wire $A$) and aluminium (wire $B$) of equal lengths as shown in Figure. The cross-sectional areas of wires $A$ and $B$ are $1.0 \; mm^{2}$ and $2.0 \; mm^{2}$ respectively. At what point along the rod should a mass $m$ be suspended in order to produce $(a)$ equal stresses and $(b)$ equal strains in both steel and aluminium wires?

What is the tangential stress on the cross-section $PQRS$?

Match the type of elasticity involved:

System	Type of Elasticity
$(i)$ Suspension fibre of galvanometer	$(a)$ Linear
$(ii)$ Bending of beam	$(b)$ Shear
$(iii)$ Cutting piece of paper	$(c)$ Bulk
$(iv)$ Mechanical waves in fluid	$(d)$ Shear