State what Hooke’s law says.
Fig. 3.1 shows how the applied force changes with extension for a sample of material.
On the line in Fig. 3.1, place a cross $(\times)$ to indicate the limit of proportionality. Add the label P to this cross.
On the line in Fig. 3.1, place a cross $(\times)$ to indicate the elastic limit. Label the cross with the letter E.
The sample in (b) has a cross-sectional area of $0.40\,\text{mm}^2$ and a starting length of $3.2\,\text{m}$. For deformations that stay within the limit of proportionality of the sample, determine:
the spring constant of the sample.
the Young modulus of the material used to make the sample.
Estimate the work done on the sample as it is stretched from zero extension to its breaking point. Explain how you reached your answer.
A second sample of the same material has a larger cross-sectional area than the original sample, but the same initial length. Both samples are deformed within the limit of proportionality. State and explain qualitatively how the spring constant of the second sample compares with that of the original sample.