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→Using v, u a and s
<math>u \approx 11m/s</math>
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{| class="wikitable"
| style="height:20px; width:300px; text-align:center;" |A car travelling at 30m/s has a stopping distance of 55m. Calculate the [[deceleration]] of the car correct to two [[Significant Figures|significant figures]].
| style="height:20px; width:300px; text-align:center;" |A formula 1 car is travelling at 50m/s on a straight but must slow to 22m/s for an approaching corner. The breaks can [[decelerate]] the car at 30m/s/s. Calculate how far before the [[corner]] the car must begin braking, correct to two [[Significant Figures|significant figures]].
|-
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities'''
v = 0m/s
u = 30m/s
s = 55m
| style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities'''
v = 22m/s
u = 50m/s
a = -30m/s/s
|-
| style="height:20px; width:300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers and [[Evaluate (Maths)|evaluate]].'''
<math>v^2=u^2 + 2as</math>
<math>0^2=30^2 + 2 \times a \times 55</math>
<math>0=900+110a</math>
| style="height:20px; width:300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers and [[Evaluate (Maths)|evaluate]].'''
<math>v^2=u^2 + 2as</math>
<math>22^2=50^2 + 2 \times (-30) \times s</math>
<math>484=2500 - 60s</math>
|-
| style="height:20px; width:300px; text-align:left;" |'''3. [[Rearrange (Maths)|Rearrange]] the equation and [[Solve (Maths)|solve]].'''
<math>110a = -900</math>
<math>a =\frac{-900}{110}</math>
<math>a =\frac{-900}{110}</math>
<math>a=-8.1818m/s/s</math>
<math>a \approx -8.2m/s/s </math>
Deceleration = + 8.2m/s/s
| style="height:20px; width:300px; text-align:left;" |'''3. [[Rearrange (Maths)|Rearrange]] the equation and [[Solve (Maths)|solve]].'''
<math>484=2500 - 60s</math>
<math>60s = 2500-484</math>
<math>s =\frac{2016}{60}</math>
<math>s=33.6m</math>
<math>s \approx 34m</math>
|}