(a)[1]
State the law that gives the relationship between $F$ and $x$ in Fig. 5.1.
(b)
The wire’s extension is $0.48\,\text{mm}$. Determine:
(b(i))[2]
the stress quantity.
(b(ii))[2]
the strain value.
(c)[3]
The resistivity of the wire’s metal is $3.7 \times 10^{-7}\,\Omega\,\text{m}$. Determine the change in resistance of the wire when the extension $x$ changes from $x = 0.48\,\text{mm}$ to $x = 0.60\,\text{mm}$.
(d)[1]
A force greater than $45\,\text{N}$ is now applied to the wire. Describe how it can be checked that the elastic limit of the wire has not been exceeded.