A wire with length $L$ is stretched so that its limit of proportionality can be found. The graph illustrates how the extension $x$ changes as the force $F$ applied to the wire changes. On the graph, point $P$ marks the limit of proportionality. The test is then carried out again using a different wire of length $2L$, made from the same material and having the same diameter as the first wire. Which point on the graph indicates the limit of proportionality for the new wire?
Physics 9702 · AS & A Level · Elastic and plastic behaviour