.5 Acceleration

• The average acceleration of an object can be calculated using the equation: 


  acceleration = change in velocity / time taken
• a  = ∆ v / t

  acceleration, a, in metres per second squared, m/s2

  change in velocity, ∆v, in metres per second, m/s

  time, t, in seconds, s
• An object that slows down is decelerating
• The following equation applies to uniform acceleration:

  (final velocity)^2 − (initial velocity)^2 = 2 × acceleration × distance
• v^2 −  u^2 = 2 a s

  final velocity, v, in metres per second, m/s

  initial velocity, u, in metres per second, m/s

  acceleration, a, in metres per second squared, m/s2

  distance, s, in metres, m
• Near the Earth’s surface any object falling freely under gravity has an acceleration of about 9.8 m/s2
• An object falling through a fluid initially accelerates due to the force of gravity. Eventually the resultant force will be zero and the object will move at its terminal velocity