CP2 Flashcards
Acceleration
A measure of how quickly the speed of something is changing.
Balanced forces
When the forces in opposite directions on an object are the same size so the result force is zero.
Resultant force
The total force that results form two or more forces acting upon a single object. It is found by adding together the forces, taking into account their directions.
Unbalanced forces
When the forces in opposite directions on an object do not cancel out.
Centripetal force
A force that causes objects to follow a circular path. The force acts towards the center of the circle.
Gravitational field strength
A measure of how strong the force of gravity is somewhere. It is the force on a 1kg mass, so the units are newtons per kilogram (N/kg).
Inertial mass
The mass of an object found from the ratio of force divided by acceleration.
Action-reaction forces
Pairs of forces on interacting objects. Action reaction forces are always the same size, in opposite directions and acting on different objects.
Equilibrium
When a situation is not changing because all the things affecting it balance out.
Conservation of momentum
The total momentum of moving objects before a collision is the same as the total momentum afterwards, as long as no external forces are acting.
Thinking distance
The distance travelled by a vehicle while the driver reacts.
Braking distance
The distance travelled by a vehicle while the brakes are working to bring it to a halt.
Stopping distance
The distance in which a car stops, which is the sum of the thinking and braking distances.
Reaction time
The time taken to respond to a stimulus.
Stimulus
Something outside the body that can be detected by the body, such as a sight or sound.
