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: u = initial [[speed]]
: t = [[time]]
===Example Calculations===
{| class="wikitable"
|-
| style="height:20px; width:300px; text-align:center;" |'''A person starts at rest and accelerates to a [[speed]] of 8m/s in 0.8 [[second]]s. Calculate the acceleration of the person.'''
| style="height:20px; width:300px; text-align:center;" |'''A racing car travels comes around a corner at a [[speed]] of 20m/s and in 1.5 [[second]]s accelerates to a [[speed]] of 80m/s. Calculate the acceleration of the racing car.'''
|-
| style="height:20px; width:300px; text-align:left;" |
final speed = 8[[m/s]]
initial speed = 0[[m/s]]
time = 0.8[[s]]
<math>a = {\tfrac{v-u}{t}} </math>
<math>a = {\tfrac{8-0}{0.8}} </math>
<math>a = {\tfrac{8}{0.8}} </math>
<math>a = 10m/s/s </math>
| style="height:20px; width:300px; text-align:left;" |
final speed = 80[[m/s]]
initial speed = 20[[m/s]]
time = 1.5[[s]]
<math>a = {\tfrac{v-u}{t}} </math>
<math>a = {\tfrac{80-20}{1.5}} </math>
<math>a = {\tfrac{60}{1.5}} </math>
<math>a = 40m/s/s </math>
|-
| style="height:20px; width:300px; text-align:center;" |'''A [[horse]] begins trotting at 3.0m/s and accelerates to canter at 11m/s in 2.0 [[second]]s. Calculate the acceleration of the [[horse]].
| style="height:20px; width:300px; text-align:center;" |'''A space probe is travelling at 18,000m/s and uses a thruster for 250 [[second]]s to slow down to 6,000m/s. Calculate the acceleration of the space probe.'''
|-
| style="height:20px; width:300px; text-align:left;" |
final speed = 11[[m/s]]
initial speed = 3.0[[m/s]]
time = 2.0[[s]]
<math>a = {\tfrac{v-u}{t}} </math>
<math>a = {\tfrac{11-3.0}{2.0}} </math>
<math>a = {\tfrac{8.0}{2.0}} </math>
<math>a = 4m/s/s </math>
| style="height:20px; width:300px; text-align:left;" |
final speed = 18,000[[m/s]]
initial speed = 6,000[[m/s]]
time = 250[[s]]
<math>a = {\tfrac{v-u}{t}} </math>
<math>a = {\tfrac{18,000-6,000}{250}} </math>
<math>a = {\tfrac{12,000}{250}} </math>
<math>a = 48m/s/s </math>
|}
==Key Stage 4==
===Meaning===
'''Acceleration''' is a [[vector]] quantity that describes a change in [[velocity]].
===About Acceleration===
: [[Acceleration]] is a [[vector]] because it has a [[magnitude]] and direction.
: The [[SI Unit]]s of [[acceleration]] and metres per second per second (m/s/s).
[[Acceleration]] may refer to:
*Increasing [[speed]] - The [[magnitude]] of the [[velocity]] increases.
*Decreasing [[speed]] - The [[magnitude]] of the [[velocity]] decreases, also known as [[deceleration]].
*Changing direction - The [[magnitude]] of the [[velocity]] remains constant (constant [[speed]]) but the [[object]] changes direction of travel.
: [[Acceleration]] occurs due to [[Unbalanced Forces|unbalanced forces]] on an [[object]].
===Examples===
{| class="wikitable"
|-
|[[File:Rollers.gif|center]]
|[[File:CircularMotion.gif|center]]
|-
| style="height:20px; width:200px; text-align:center;" |This animation shows a [[linear]] [[acceleration]] as the [[object]]s roll down the slope.
| style="height:20px; width:200px; text-align:center;" |This animation shows [[acceleration]] due to a changing direction.
|}
===Equation===
====Acceleration, Velocity and time====
''NB: You must remember this equation.''
This equation applies to [[linear]] [[acceleration]] but not to a change in direction.
<math>a = {\tfrac{\delta v}{t}} </math>
Where:
<math>a</math> = [[Acceleration]] of the [[object]].
<math>\delta v</math> = Change in [[magnitude]] of the [[velocity]].
<math>t</math>= [[Time]] taken for the change in [[velocity]].
===Example Calculations===