Part A

$\overline{){\mathbf{S}}{\mathbf{t}}{\mathbf{r}}{\mathbf{a}}{\mathbf{i}}{\mathbf{n}}{\mathbf{}}{\mathbf{=}}\frac{\mathbf{\u2206}\mathbf{L}}{\mathbf{L}}}$

ΔL = 1 mm = 1 × 10^{-3} m

L = 4 m

Part A

If a metal wire is 4 m long and a force of 5000 N causes it to stretch by 1 mm, what is the strain?

a. 0.25

b. 1 mm

c. 0.00025

d. The answer can’t be found without knowing the area.

Part B

The maximum stress a bone can experience before it fractures is around 108 N/m^{2}. How much stress could the bone experience if it were twice as large in diameter?

a. The maximum stress would be no different.

b. The stress would be one-fourth as large.

c. The stress would be twice as large.

d. The stress would be half as large.

Part C

A metal bar is elongated by 2 mm when put under a certain amount of tension. How much will it be elongated if the tension is doubled?

a. 1 mm

b. 4 mm

c. 2 mm (It would not change.)

d. This question can’t be answered without knowing the stress.

Part D

The Young’s modulus of aluminum is 69 GPa, of nylon is 3 GPa, of tungsten is 400 GPa, and of copper is 117 GPa. If equal-size samples were put under equivalent tensile stresses, how would you rank the materials by the degree to which they would be elongated?

Rank the wires from least elongation (least stretch) to most elongation (most stretch).

Copper

Nylon

Tungsten

Aluminum

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Stress & Strain concept. If you need more Stress & Strain practice, you can also practice Stress & Strain practice problems.