AQA GCSE: Physics

Simple Electric Circuits

  • Current (I): flow of charge (amps, A)

  • Voltage (V): energy transferred per charge (volts, V)

  • Resistance (R): opposition to current (ohms, Ω)

  • Series circuits:

    • Same current everywhere

    • Voltage shared

    • Total resistance = sum


  • Parallel circuits:

    • Same voltage

    • Current splits

    • Lower total resistance



Atoms and Materials

Atomic Structure

  • Proton (+1), neutron (0), electron (–1)

  • Nucleus contains protons & neutrons

  • Electrons in shells


States of Matter

  • Solid → fixed shape & volume

  • Liquid → fixed volume, no fixed shape

  • Gas → no fixed shape or volume


Changes of State

  • Melting, freezing, evaporation, condensation, sublimation

  • Internal energy = kinetic + potential energy of particles


Forces

Types of Forces

  • Gravity, friction, air resistance, tension, normal contact force


Electricity in the Home

  • UK mains supply: 230 V AC, 50 Hz

  • Live wire: brown

  • Neutral wire: blue

  • Earth wire: green/yellow (safety)

  • Fuse: melts if current too high → breaks circuit

  • Double insulation: plastic casing, no earth needed


Energy Resources

Renewable

  • Solar, wind, hydro, tidal, geothermal, biofuel


Non-renewable

  • Coal, oil, gas, nuclear


Energy Stores

  • Thermal, kinetic, chemical, gravitational, elastic, nuclear


Power Stations

  • Fuel → boil water → steam → turbine → generator


Atoms and Radiation

Isotopes

  • Same protons, different neutrons


Radiation Types

Type

What it is

Stopped by

Ionising

Alpha (α)

2p + 2n

Paper/skin

Very

Beta (β)

Electron

Aluminium

Medium

Gamma (γ)

EM wave

Lead/concrete

Weak


Half-life

  • Time taken for radioactive substance to halve in activity


Uses

  • Medical tracers, cancer treatment, smoke detectors, carbon dating


Risks

  • Cell damage, mutations, cancer


Waves

Types

  • Transverse: oscillations perpendicular (light, water)

  • Longitudinal: oscillations parallel (sound)


Wave Properties

  • Amplitude, wavelength, frequency, speed


Reflection & Refraction

  • Reflection → bouncing off surface

  • Refraction → bending when entering different medium


Sound Waves

  • Longitudinal, need medium, faster in solids


Uses & Dangers

  • Microwaves → cooking

  • Infrared → heaters

  • UV → sterilising (skin damage risk)

  • X-rays → medical imaging

  • Gamma → cancer treatment



Key Formula List