Which statement about electric current in a metallic conductor is correct?
In a direct current (d.c.) circuit, the net flow of free electrons is continuously in one direction.
In an alternating current (a.c.) circuit, the free electrons travel all the way from the power supply to the load in each cycle.
In a direct current (d.c.) circuit, the current gradually decreases in magnitude as it passes through successive components.
In an alternating current (a.c.) circuit, the free electrons drift in a single direction with a constantly increasing speed.
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.