(a)[2]
Calculate the extension of the spring when the applied load is $3.0\,\text{N}$.
(b)[2]
Explain what the term limit of proportionality of the spring means.
(c)[2]
On Fig. 1.2, sketch an extension-load graph for a spring. Put the letter L on your graph to show the limit of proportionality.
(d)[3]
The load is pulled a short distance below the equilibrium position to point A, as shown in Fig. 1.3. It then oscillates up and down between A and B in Fig. 1.3. Describe the energy changes that happen as the load travels: from A to the equilibrium position from the equilibrium position to B.