SUVAT equations: v = u + at, s = ut + ½at²
The SUVAT equations are v = u + at; s = ut + ½at²; v² = u² + 2as; s = ½(u + v)t; s = vt − ½at².
What each letter means
- \(s\) displacement
- \(u\) initial velocity
- \(v\) final velocity
- \(a\) acceleration (constant)
- \(t\) time
When to use it
For motion in a straight line with constant acceleration, including objects falling freely under gravity.
Worked example
A car moving at \(4\text{ m s}^{-1}\) accelerates uniformly at \(1.5\text{ m s}^{-2}\) for 6 s. Find its final speed and the distance travelled.
- \(v=4+1.5\times6\)
- \(s=4\times6+\tfrac12\times1.5\times6^2=24+27\)
Answer: \(v=13\text{ m s}^{-1}\), \(s=51\) m
Common mistake
Using them when the acceleration is not constant. Then you need calculus: v = ds/dt, a = dv/dt.
On your course
| Course | In the exam |
|---|---|
| Edexcel A Level (9MA0) | In the Edexcel formulae booklet |
| Edexcel International A Level | Not in the booklet: learn it |
| AQA or OCR A Level | Check your board’s formula booklet: AQA formulae booklet (PDF) · OCR A Level Maths assessment page |
From our own A Level Maths formula sheets, in our words. Official: Pearson's formulae booklet (PDF) · Pearson's IAL formulae booklet (PDF).
Practise and revise
- Practise A Level Maths practice
- Revise Kinematics
- Revise IAL M1 kinematics
- Print Edexcel A Level (9MA0) one-page formula sheet
Questions
What is the SUVAT equations formula?
The SUVAT equations are v = u + at; s = ut + ½at²; v² = u² + 2as; s = ½(u + v)t; s = vt − ½at². s: displacement; u: initial velocity; v: final velocity; a: acceleration (constant); t: time.
Is the SUVAT equations given in the exam?
Edexcel A Level (9MA0): in the Edexcel formulae booklet. Edexcel International A Level: not in the booklet: learn it. AQA or OCR A Level: check your board’s formula booklet. This comes from our own A Level Maths formula sheets; your teacher has the official booklet.
Which suvat equation should I use?
Write down the three quantities you know and the one you want. Use the equation that contains exactly those four letters.
Our own wording, examples and card, checked by A Level Math Revision. Not produced or endorsed by Pearson Edexcel, AQA or OCR.