Momentum Simulation — Description & Classroom Activity Guide
What the Simulation Does
The simulation has four tabs, each isolating one core GCSE momentum concept with moving objects and live calculations.
⚡ What is p? A single ball rolls across the screen at constant speed. As it travels, its mass and velocity labels float above it, then a yellow momentum arrow grows beneath the floor and the equation builds step-by-step: p = mv → p = 2 × 5 → p = 10 kg·m/s. Students see the formula come alive rather than just reading it.
⚖️ Mass tab Two balls roll side-by-side at identical speeds — students can visibly confirm both are moving at the same rate. The smaller ball (2 kg) hits a stack of crates and barely disturbs them. The larger ball (5 kg) scatters five crates much further. Momentum arrows then appear showing 8 vs 20 kg·m/s at the same scale, making the proportional difference visible.
🐇 Speed tab Two identical-size balls (same mass, 3 kg) leave the starting line together. The fast ball (6 m/s) races to the right three times faster than the slow one (2 m/s) — the gap between them grows dramatically. Momentum arrows show 6 vs 18 kg·m/s.
💥 Collision tab Trolley A rolls right and hits stationary Trolley B. In a perfectly elastic equal-mass collision, A stops dead and B shoots off at the same speed. The momentum arrow transfers from A to B and the conservation badge confirms: p before = p after = 20 kg·m/s.
The fact bar at the bottom updates automatically as each scene progresses, walking students through the calculation in three stages — question, working, conclusion.
Suggested Classroom Activities
Starter — Predict Before You Play (5 min) Before opening the Mass tab, pose the question to the class: “If I double the mass but keep the speed the same, what happens to momentum?” Take a show of hands, then play the simulation. The visual of the crates scattering gives instant feedback on who predicted correctly.
Paired Pause Activity (10 min) Put students in pairs. One student runs the simulation using the Accessibility → Pause toggle to freeze it at different moments. The other student must write down the values they see on screen and calculate momentum using p = mv before they’re allowed to unpause. Works especially well on the Speed tab where the two arrows appear at different times.
Live Calculation Race (10 min) Teacher controls the simulation on the board. Stop on the Mass tab just before the momentum arrows appear. Students race to calculate both momentum values (2 × 4 and 5 × 4) on mini whiteboards. Reveal the arrows to self-check. Repeat with the Speed tab (3 × 2 and 3 × 6).
Conservation Investigation (15 min) Use the Collision tab with the Very Slow speed setting (Accessibility drawer) so students can observe the full sequence carefully. Ask students to: (1) record momentum of A before collision, (2) record momentum of B after, (3) explain in one sentence why the numbers are equal. This directly addresses the GCSE required practical link to momentum conservation.
Exit Ticket Display this on the board after the lesson: “A 3 kg skateboard moves at 4 m/s. A 6 kg skateboard moves at 2 m/s. Which has more momentum? Show your working.” Students who watched the simulation carefully should recognise immediately that both have p = 12 kg·m/s — a deliberate trick that tests whether they’ve actually internalised the formula rather than just the visual pattern.