a. Explain why the resistance of a metal increases when its temperature increases.
b. State two other factors that determine the resistance of a stated length of wire.
c. When a potential difference of 1.5 V is applied across a 5.0 m length of insulated copper wire, a current of 0.24 A is measured in it.
i. Calculate the resistance of the length of wire.
ii. The resistivity of copper is 1.69 × 10⁻⁸ Ω m. Calculate the diameter of the wire.
d. The wire is now made into a tight bundle. State and explain how you would expect the current in it to change.