PhysicsQ&A by dot point

Newton's laws: balanced and unbalanced forces, Newton's first and second laws including F equals ma, the difference between mass and weight, and friction and free-body force diagrams.

Projectile motion: treating a projectile as separate horizontal (constant velocity) and vertical (constant acceleration) motions, and using these to find the range, time of flight and impact velocity.

Vectors and scalars: distinguishing the two kinds of quantity, the difference between distance and displacement and between speed and velocity, and combining vectors that act at right angles.

Velocity and acceleration: defining and calculating acceleration, and interpreting velocity-time graphs to describe motion and to find acceleration and distance travelled.

Energy: work done by a force, gravitational potential energy and kinetic energy, the conservation of energy, and using energy changes to solve motion problems such as a falling or braking object.

Electrical charge carriers: current as the flow of charge, the relationship between charge, current and time, the role of electrons as charge carriers, and how current divides in series and parallel circuits.

Electrical power: power as energy transferred per second, the relationships linking power to current, voltage and resistance, and using power to find the energy and cost of running an appliance.

Ohm's law: the relationship between voltage, current and resistance, the meaning of resistance, and calculating the total resistance of resistors in series and in parallel.

Potential difference (voltage): voltage as the energy given to each unit of charge, the relationship between energy, charge and voltage, and how voltage behaves in series and parallel circuits.

Practical electrical and electronic circuits: standard circuit symbols and components, input and output devices such as the LDR and thermistor, the potential divider, and the action of switches and simple control circuits.

Gas laws and the kinetic model: the relationships between the pressure, volume and temperature of a fixed mass of gas, the kelvin temperature scale, and the kinetic model explanation of gas pressure.

Pressure: the definition of pressure as force per unit area, the relationship linking pressure, force and area, the unit of pressure, and everyday and gas-pressure examples.

Specific heat capacity: the energy needed to change the temperature of a material, the relationship linking energy, mass, specific heat capacity and temperature change, and using it in heating and mixing problems.

Specific latent heat: the energy needed to change the state of a material without changing its temperature, the relationship linking energy, mass and specific latent heat, and the difference between latent heat of fusion and of vaporisation.

Dosimetry: absorbed dose as energy per unit mass, equivalent dose using the radiation weighting factor, equivalent dose rate, the safe handling of sources, and background radiation.

Half-life: the meaning of half-life, how activity and the number of undecayed nuclei fall by half each half-life, finding half-life from data or a graph, and uses such as dating and medical tracers.

Nuclear radiation: the nature and properties of alpha, beta and gamma radiation, their ionising ability and penetrating power, what ionisation means, and the activity of a source.

Cosmology: using the electromagnetic spectrum and telescopes to study the universe, line spectra as a fingerprint of elements, and redshift as evidence that the universe is expanding.

Space exploration: rocket thrust and Newton's third law, weight and mass on different bodies, the use of satellites and the idea of a satellite as a projectile, and the risks and benefits of space travel including re-entry heating.

The electromagnetic spectrum: the order of the bands by wavelength and frequency, that all travel at the speed of light, and the uses, sources and detectors of each band including the dangers of the high-energy bands.

Refraction of light: the change of direction when light crosses a boundary between materials, the angles of incidence and refraction, why refraction happens, and the action of a lens and total internal reflection.

Wave parameters and behaviours: the meaning of wavelength, frequency, period, amplitude and speed, the wave equations, the difference between transverse and longitudinal waves, and wave behaviours such as reflection and diffraction.