Young's Modulus — Prelims Questions

A steel wire of length $L$ and cross-sectional area $A$ is stretched by a force $F$. If Young's Modulus for steel is $Y$, what is the elongation of the wire?

Two wires A and B are made of the same material. Wire A has length $L$ and radius $r$, while wire B has length $2L$ and radius $2r$. If both wires are stretched by the same force $F$, what is the ratio of elongation of wire A to wire B ($\Delta L_A / \Delta L_B$)?

Which of the following statements about Young's Modulus is INCORRECT?

A metal rod of length $1,\text{m}$ and diameter $2,\text{cm}$ is subjected to a tensile force of $10,\text{kN}$. If the elongation produced is $0.5,\text{mm}$, calculate the Young's Modulus of the material.

A stress-strain curve for two materials P and Q is shown. If the curves are linear up to their respective fracture points, and the curve for P is steeper than Q, which material is more ductile?

A wire elongates by $1,\text{mm}$ when a load $W$ is suspended from it. If the same wire is replaced by another wire of the same material but half the length and double the radius, what will be the elongation when the same load $W$ is suspended?