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| style="height:20px; width:400px; text-align:center;" |The equation for '''kinetic energy''' written in symbols.
|}
===Calculating Kinetic Energy===
{| class="wikitable"
| style="height:20px; width:200px; text-align:center;" |A 700kg formula one racing car has a top speed of 100m/s. Calculate the '''kinetic energy''' of the [[car]] to two [[Significant Figures|significant figures]].
| style="height:20px; width:200px; text-align:center;" |A cheetah of mass 75kg runs at a speed of 32m/s. Calculate the '''kinetic energy''' of the [[cheetah]] correct to two [[Significant Figures|significant figures]].
| style="height:20px; width:200px; text-align:center;" |A 160g cricket ball is hit at 44m/s. Calculate the '''kinetic energy''' of the cricket ball correct to two [[Significant Figures|significant figures]].
|-
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
m = 700kg
v = 100m/s
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
m = 75kg
v = 32m/s
| style="height:20px; width:200px; text-align:left;" |'''1. State the known quantities'''
m = 160g
'''Convert [[mass]] into [[kilogram]]s.'''
<math>m = \frac{160}{1000}</math>
m = 0.16kg
v = 32m/s
|-
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
<math>E_k = \frac{1}{2} m v^2</math>
<math>E_k = \frac{1}{2} \times 700 \times 100^2</math>
<math>E_k = \frac{1}{2} \times 700 \times 10,000</math>
<math>E_k = 3,500,000J</math>
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
<math>E_k = \frac{1}{2} m v^2</math>
<math>E_k = \frac{1}{2} \times 75 \times 32^2</math>
<math>E_k = \frac{1}{2} \times 75 \times 1024</math>
<math>E_k = 38,400J</math>
<math>E_k \approx 38000J</math>
| style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].'''
<math>E_k = \frac{1}{2} m v^2</math>
<math>E_k = \frac{1}{2} \times m \times v^2</math>
<math>E_k = \frac{1}{2} \times 0.16 \times 44^2</math>
<math>E_k = \frac{1}{2} \times 0.16 \times 1936</math>
<math>E_k = 154.88J</math>
<math>E_k \approx 150J</math>
|}
==Key Stage 4==
===Meaning===
The '''kinetic energy store''' is the [[Energy Store|energy store]] associated with moving [[object]]s.
===About Kinetic Energy===
: Any moving [[object]] stores '''kinetic energy'''.
: The '''kinetic energy store''' of an [[object]] is related to two [[property|properties]] of the [[object]]:
*The [[mass]] of the [[object]] - The greater the [[mass]] the greater the '''kinetic energy''' stored.
*The [[speed]] or [[velocity]] of the [[object]] - The greater the [[speed]] the greater the '''kinetic energy''' stored.
===Equation===
''NB: You must memorise this equation!''
'' '''Kinetic Energy''' = 0.5 x (Mass) x (Speed)<sup>2</sup>''
<math>E_k = \frac{1}{2} m v^2</math>
Where:
E<sub>k</sub> = '''Kinetic Energy''' stored.
m = The [[mass]] of the [[object]].
v = The [[speed]] or [[velocity]] of the [[object]].
===Calculating Kinetic Energy===