Force, mass and acceleration

One law, three dials. Push the block and watch it answer — then work out why doubling the mass needs double the force to feel the same.

Playable Class 11 · Physics Laws of Motion Runs in your browser

Chart · does acceleration really track force?

Every force you dial in drops a point on this chart. If the law holds, the points should fall on a straight line through zero — and the line should get flatter as you add mass.

Try this before you scroll on. Leave the force at 30 N. Set the mass to 3 kg, then 6 kg, then 12 kg. The force never changed — so what exactly did the acceleration do each time, and why does the chart line tilt the way it does?

Controls

Mass 6.0 kg Force 24 N Friction 6 N

Live readout

Time: 0.0s
Position: 4.0m
Velocity: 0.00m/s
Accel.: 0.00m/s²
Net force: 0N
Slope 1/m: 0.00kg⁻¹

What the simulation actually does

Friction always pushes back against the direction of travel, and it can never push the block forwards. If your force is smaller than friction and the block is already still, it stays still — which is the part most diagrams leave out.

The block stops dead at the end of the track, so give it room. Values are for teaching: the surface is level and air resistance is ignored.