IGCSE Physics Revision Notes - Electricity & Magnetism

These flashcards cover key concepts related to electricity and magnetism, including definitions, laws, formulas, and the functions of devices used in electrical circuits.

What are the two types of magnets?

Permanent magnets and induced magnets.

What is the law of magnetism regarding poles?

Opposite poles attract and like poles repel.

What is the role of a solenoid in magnetism?

A solenoid is a coil of wire that produces a magnetic field when electric current passes through it.

What is Ohm's law?

Ohm's law states that the current (I) is directly proportional to the potential difference (V) across a conductor, as long as the temperature remains constant, represented by the equation R = V/I.

What is the formula for calculating electrical energy?

E = VIt, where E is energy in joules, V is voltage in volts, I is current in amps, and t is time in seconds.

What is the difference between direct current (DC) and alternating current (AC)?

DC is a constant flow of electric charge in one direction, while AC is an electric charge that changes direction periodically.

How does a transformer work?

A transformer works by inducing a voltage in the secondary coil through a changing magnetic field created by an alternating current in the primary coil.

What does Lenz's law state?

Lenz's law states that the direction of an induced potential difference always opposes the change that produces it.

In electrical circuits, what is the function of a fuse?

A fuse is a safety device that cuts off the flow of electricity if the current exceeds a certain level, protecting the circuit.

What are characteristics of a parallel circuit?

In a parallel circuit, the total current splits among the branches, components can be individually controlled, and if one component fails, others continue to work.