Motion (3.1)

Displacement

The distance travelled in a particular direction

Displacement is a vector quantity, which means what?

It has direction and magnitude

Instantaneous speed

The rate of change of distance at a specific moment in time

How can instantaneous speed be calculated

Change is distance divided by an infinitesimal interval of time

Average speed

The rate of change of distance calculated over a complete journey

Velocity

The rate of change of displacement

Is velocity a vector or scalar quantity?

Vector

Average velocity

The change in displacement for a journey divided by the time taken

Stopping distance

The distance travelled until the car stops

How can stopping distance be calculated?

Thinking distance + braking distance

Thinking distance

The distance travelled while the driver reacts

Braking distance

The distance travelled between the instant the brakes are applied and the instant the vehicle stops completely

Free fall

The motion of an object accelerating under gravity with no other significant forces acting on it

Projectile

An object that is thrown on the surface of the Earth

Time of flight

The duration of an object’s free movement through a fluid