Charge flow in a circuit
Charge flow in a circuit
A circuit is a closed loop that lets charge move. In metal wires the moving particles are electrons, but conventional current is defined as the direction positive charge would flow.
Step-by-step lessons on Edexcel A Level Physics Current, potential difference and resistance. Each one builds up to exam-style questions. Physics is one of the most mathematically demanding A Levels -- at least 40% of the marks across the three papers require maths skills at Level 2 (GCSE) standard or above, so build calculation and graph-handling fluency alongside the conceptual content from the start.