This question is about electric circuits.
State the name of the instrument used to measure electric current in a circuit.
State the SI unit of electrical resistance.
A student connects a circuit to determine the resistance of a wire. The current in the wire is 0.30 A0.30\text{ A}0.30 A when the potential difference across the wire is 7.5 V7.5\text{ V}7.5 V.
Calculate the resistance of the wire.
The student has several wires of the same material as the one in (b)(i) but with various lengths and thicknesses. She wants to use a wire that has a lower resistance than the wire in (b)(i).
State two ways she can identify a wire with a lower resistance by comparing its length and thickness to the wire in (b)(i).
132 exam-style questions on CIE IGCSE Physics 4.2.4a Resistance. Each one has a worked solution and a mark scheme showing where the marks go.