Forces Glossary

Question 1

Acceleration

Answer 1

The rate of change of velocity. It can be calculated from the gradient of a velocity-time graph.

Question 2

Atmosphere

Answer 2

The thin layer of air surrounding the Earth, which gets less dense with increasing altitude

Question 3

Braking distance

Answer 3

The distance a vehicle travels under the braking force. This can be affected by adverse road and weather conditions as well as the condition of the vehicle.

Question 4

Centre of mass

Answer 4

The single point through which the weight of the object can be said to act

Question 5

Changes of momentum

Answer 5

When a force acts on a moving object, or an object that has the ability to move, a change of momentum will occur. The force is equal to the rate of change of momentum

Question 6

Conservation of momentum

Answer 6

The total momentum of a system before an event is always equal to the total momentum of the system after the event

Question 7

Conatact forces

Answer 7

A force that occurs when objects are physically touching

Question 8

Displacement

Answer 8

A measure of how far an object moves in a given direction. It is the straight line between the starting and finishing points, and it is a vector quantity.

Question 9

Distance

Answer 9

A measure of how far an object moves, that does not depend on direction and is therefore a scalar quantity.

Question 10

Elastic deformation

Answer 10

Non-permanent deformation, which allows the object to return to its original shape when the deforming forces are removed

Question 11

Elastic limit

Answer 11

The force beyond which an object will no longer deform elastically and will instead deform plastically.