Fig. 2.1 shows the extension-load graph for a spring. extension
06
load
Fig. 2.1
Dint P is the limit of proportionality.
:) (0) Name the law obeyed by the spring from the origin to P.
[1]
(ii) Describe two features of the graph which show that the law is obeyed.
2.
[2]
-) On Fig. 2.1, sketch a possible continuation of the graph when the spring is loaded
beyond the limit of proportionality.

(1) Hooke's law

(2) a) Extension is directly proportional to the applied load

b) The starting point of the graph is the origin (0, 0) or absence of load, no extension

Explanation:

(1) The law obeyed by the spring is known as Hooke's law which states that the extension or compression, x, of a spring proportional to the applied force, F

F = -k × x

Where;

k = The spring constant

(2) Given that the law mathematically is F = -k × x

The two features of the graph that show that the law is obeyed are;

a) The extension increases as the load is increased

b) The extension is zero when the there is no applied load.