Work, energy and momentum

What do we mean by 'work' in science?

What is the relationship between work and energy?

How do we calculate the work done by force?

What happens to work done to overcome friction?

What does the gravitational potential energy of an object depend on?

How can we calculate the change of gravitational potential energy of an object when it moves up or down?

What does the kinetic energy of an object depend on?

How can we calculate kinetic energy?

What is elastic potential energy?

How can we calculate momentum?

What is the unit of momentum?

Why does momentum have a direction as well as a size?

When two objects push each other apart do they move away at different speeds?

When two objects push each other apart why is their momentum zero?

When vehicles collide, what does the force of impact depend on?

How does the impact force depend on the impact time?

What can we say about the impact forces and the total momentum when two vehicles collide?

Why do seat belts and air bags reduce the force on people in car accidents?

How do side impact bars and crumple zones work?

How can we work out if a car in a crash was 'speeding'?