Push and Pull Simulation — Description
Simulation description
This interactive force simulation lets students visualise how push and pull forces act on an object in real time. Using the three sliders, learners can independently control the magnitude of a push force (red, acting left to right), a pull force (green, acting right to left), and the object’s mass. The canvas shows proportional force arrows, a motion trail, and live readouts of net force and acceleration calculated from Newton’s Second Law (F = ma). When push and pull are equal, the object reaches equilibrium. Students can also drag the object directly to reposition it and observe how forces immediately take effect.
Class Activity — “Find the Balance”
Level: KS4 / GCSE Physics Time: 15–20 minutes Group size: Pairs
Task
Students work through three challenges using the simulation:
- Equilibrium Hunt — Set any push force value, then adjust pull until the object stops moving. Record the matching values and confirm they are equal. Discuss what this means for net force.
- Mass vs. Acceleration — Fix push at 60 N and pull at 0 N. Increase mass from 1 kg to 20 kg in steps. Record acceleration at each step and plot a graph of acceleration against mass. What shape does it make?
- Tug of War — Set push to 80 N and pull to 50 N. Predict which direction the object will move and how fast before releasing it. Check against the simulation. Then swap the values and repeat.
Discussion prompts
- What happens to acceleration when you double the mass but keep force the same?
- Can you have motion with zero net force?
- How does this connect to a real tug of war or a car braking?
Assessment hook — Ask students to screenshot one scenario, annotate the force arrows, and write one sentence explaining what F = ma tells them about that moment.