Physics Simulations
Interactive simulations based on past paper questions. Click one to open it.
Microwave Interference from a Moving Reflector
Explore how microwave interference changes when a metal reflector is moved. The receiver detects both a direct and a reflected microwave. As the reflector moves, the path difference changes, producing alternating maxima and minima that demonstrate constructive and destructive interference.
Investigating Stopping Potential: The Photoelectric Effect
Explore how stopping potential is used to investigate the photoelectric effect. Adjust frequency, work function, reverse potential difference and light intensity to observe how photocurrent changes, and see how Einstein's photoelectric equation links photon energy, work function and maximum kinetic energy.
How a Centrifuge Works
Explore how a centrifuge separates a mixture of substances. Adjust the rotor speed (rpm), the radius and the densities of the substances to see how denser components are flung to the outside while lighter ones stay near the centre. Demonstrates centripetal acceleration and how spinning amplifies the effect of small density differences.
Drag vs Wind
Drive a car through air particles and watch the drag force grow as it speeds up. Drag is a resistive force that acts when an object moves through a fluid: it always opposes the motion, is zero when the object is stopped, and can never push it backwards. Add wind to see how moving air is a separate push, not drag.