Speed, displacement, velocity and acceleration

Speed

• How quickly an object can move from one place to another

• Speed = distance travelled (metres)/time taken (seconds)

• Unit:

  • m/s

Displacement

• Distance in a given direction

• Depends on a start and end position

• As the crow flies

Velocity

• Speed in a given direction

• Velocity = distance (metres)/time (seconds)

Acceleration

• The rate of change of speed (velocity)

• Acceleration = change in velocity (m/s)/time (seconds) = m/s²

• Getting faster = positive (+)

• Getting slower = negative (-)