Weight and mass are very different. Find out more with BBC Bitesize. For students between the ages of 11 and 14.

What happens when an unstoppable force meets an immovable object? The scientist-artists at MinutePhysics have attempted to answer this question with the magic of physics.

It demonstrates the measurements to take to calculate velocity and acceleration. Students could be asked to predict the effect of increasing mass and increasing force on acceleration of an object.

Fundamental forces of nature: Gravity Gravity is the attraction between two objects that have mass or energy, whether this is seen in dropping a rock from a bridge, a planet orbiting a star or the ...

To accurately calculate impact force, we also need to know the stopping distance of the object — that is, how far it continued to travel, penetrating or deforming the point of impact.