← Physics syllabus

SingaporePhysics

Electricity and Magnetism

7 dot points across 7 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

How are alternating currents characterised by root-mean-square values, and how do transformers change a.c. voltages?

Define peak and root-mean-square values for alternating current, relate them to power, and explain the operation of an ideal transformer
A focused answer to the H2 Physics learning outcome on alternating current. Peak and root-mean-square values, why r.m.s. matters for power, the transformer turns ratio, and the role of transformers in power transmission.
8 min answer →

How does a capacitor store charge and energy, and how do capacitors combine in circuits?

Define capacitance, calculate the energy stored on a capacitor, and combine capacitors in series and parallel
A focused answer to the H2 Physics learning outcome on capacitance. The definition Q = CV, the energy stored on a capacitor, and the rules for combining capacitors in series and parallel.
8 min answer →

What is electric current as a flow of charge, and how do resistance and resistivity describe how a conductor opposes that flow?

Define electric current, potential difference and resistance, apply Ohm's law and resistivity, and relate electrical power to current and voltage
A focused answer to the H2 Physics learning outcome on current and resistance. Current as the rate of flow of charge, potential difference, Ohm's law, resistivity, ohmic and non-ohmic behaviour, and electrical power.
8 min answer →

How do Kirchhoff's laws, built on conservation of charge and energy, let us analyse any d.c. circuit?

Apply Kirchhoff's current and voltage laws, combine resistors in series and parallel, and analyse potential dividers and the effect of internal resistance
A focused answer to the H2 Physics learning outcome on d.c. circuits. Kirchhoff's current and voltage laws, series and parallel resistor combinations, the potential divider, and electromotive force with internal resistance.
9 min answer →

How does an electric field describe the force on a charge, and how do field strength and potential relate to one another?

Define electric field strength and potential, apply Coulomb's law and the field of a point charge, and analyse the uniform field between parallel plates
A focused answer to the H2 Physics learning outcome on electric fields. Coulomb's law, electric field strength, the field and potential of a point charge, and the uniform field between charged parallel plates.
9 min answer →

How does a changing magnetic flux induce an e.m.f., and what determines its size and direction?

Define magnetic flux and flux linkage, apply Faraday's law and Lenz's law, and explain the operation of a simple generator
A focused answer to the H2 Physics learning outcome on electromagnetic induction. Magnetic flux and flux linkage, Faraday's law of induction, Lenz's law and energy conservation, and the simple a.c. generator.
9 min answer →

How does a magnetic field exert a force on a current-carrying conductor and on a moving charge?

Define magnetic flux density, calculate the force on a current-carrying conductor and on a moving charge, and analyse the circular motion of a charge in a magnetic field
A focused answer to the H2 Physics learning outcome on magnetic forces. Magnetic flux density, the force F = BIL on a current, the force F = Bqv on a moving charge, Fleming's left-hand rule, and circular motion in a field.
9 min answer →