Which of the following statements correctly describes the behavior of electric current or charge carriers in a metal conductor?
In a d.c. (direct current) circuit, the electric current decreases gradually along the length of a single uniform conductor.
In an a.c. (alternating current) circuit, the free electrons oscillate back and forth about relatively fixed positions.
In a d.c. circuit, individual electrons travel at nearly the speed of light from the negative to the positive terminal.
In an a.c. circuit, there is a net continuous flow of electrons in one direction around the circuit.
452 exam-style questions on CIE IGCSE Physics 4.2 Electrical quantities, covering 4.2.1a Positive and negative charge, 4.2.1b Charging by friction and detecting charge, 4.2.1c Electrical conductors and insulators, 4.2.1d Electric fields and electric field patterns, 4.2.2a Electric current, charge and measuring current, 4.2.2b Conduction in metals and the direction of current, 4.2.2c Direct current and alternating current, 4.2.3a Electromotive force, 4.2.3b Potential difference and voltmeters, 4.2.4a Resistance, 4.2.4b Resistance of a metallic wire, 4.2.4c Current–voltage graphs, and 4.2.5 Electrical energy and electrical power. Each one has a worked solution and a mark scheme showing where the marks go.