A student sets up a circuit to investigate how the electrical resistance of a nichrome wire varies with its length. They assemble a circuit containing a low-voltage power pack, a switch, an ammeter, a voltmeter, crocodile clips, and connecting leads.
Give the name of one additional piece of apparatus the student would need to carry out this investigation.
59 exam-style questions on Edexcel GCSE Physics 10.2 Resistance. Each one has a worked solution and a mark scheme showing where the marks go.