P2.2 - AQA GCSE Physics Unit 2 - Overview




The kinetic energy of objects speeding up or slowing down

When an object speeds up or slows down, its kinetic energy increases or decreases. The forces which cause the change in speed do so by doing work. The momentum of an object is the product of the object's mass and velocity.

Candidates should use their skills, knowledge and understanding to:

■ evaluate the benefits of different types of braking system, such as regenerative braking
■ evaluate the benefits of air bags, crumple zones, seat belts and side impact bars in cars. This should include ideas of both energy changes and momentum changes.

This section of the second unit is broken into two sections:

P2.2.1 - Forces and energy

P2.2.2 - Momentum

There is also a page suggesting practical experiments that should be carried out during the study of this section.