A large 75-kg lighting fixture can be hung from wires of identical size and shape made of aluminum, brass, or copper. The values of Young's modulus for these metals are $0.70 \times 10 ^ { 11 } \mathrm {~Pa}$ (aluminum), $0.91 \times 10 ^ { 11 } \text { (brass), and } 1.1 \times 10 ^ { 11 } \text { (copper) }$
Which wire would stretch the least distance?
A) copper
B) aluminum
C) brass
D) They will all stretch the same distance.

Question

Quizplus · Accepted Answer

The wire that would stretch the least distance is the one made of the material with the highest Young's modulus, as this modulus measures the stiffness of a material. Copper has the highest Young's modulus ($1.1 \times 10^{11} \text{ Pa}$) among the given materials, meaning it is the stiffest and thus will stretch the least under the same load.

A Large 75-Kg Lighting Fixture Can Be Hung from Wires 0.70×1011 Pa0.70 \times 10 ^ { 11 } \mathrm {~Pa}0.70×1011 Pa

A Large 75-Kg Lighting Fixture Can Be Hung from Wires $0.70 \times 10 ^ { 11 } \mathrm {~Pa}$