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Final velocity calculator

A-level Motion

One of the equations for motion in a straight line with constant acceleration (SUVAT).

v = u + a t

This free calculator is for A-level physics. Choose the quantity you want to find, enter the other values with their units, and it shows the working in the layout used in exams, with the answer to the number of significant figures you choose. The values shown are an example. Change them to your own.

Quantity to find

vFinal velocity to find 17.0 m/s

uInitial velocity

aAcceleration m/s²

tTime

Significant figures

Working

Write the equation
v = u + a t
Substitute the values
v = 5 + 2 × 6
Calculate
v = 17 m/s
Give the answer to 3 significant figures
v = 17.0 m/s

Worked example

Find v, the final velocity. Given: initial velocity u = 5.00 m/s; acceleration a = 2.00 m/s²; time t = 6.00 s.

Write the equation
v = u + a t
Substitute the values
v = 5 + 2 × 6
Calculate
v = 17 m/s
Give the answer to 3 significant figures
v = 17.0 m/s

Symbols and units

Symbol	Quantity	SI unit
v	Final velocity	m/s
u	Initial velocity	m/s
a	Acceleration	m/s²
t	Time	s

Final velocity: rearranged

To find final velocity: v = u + a t
To find initial velocity: u = v − a t
To find acceleration: a = (v − u) / t
To find time: t = (v − u) / a

Exam tip

Use it when you have no displacement in the question. Take one direction as positive and keep to it.

Common questions

What is the formula for final velocity?

The equation is v = u + a t, where v is the final velocity (m/s); u is the initial velocity (m/s); a is the acceleration (m/s²); t is the time (s).

What units should I use for final velocity?

In SI units: final velocity in m/s, initial velocity in m/s, acceleration in m/s², time in s. The calculator also accepts common alternatives such as kilometres, grams or minutes, and converts them for you.

How do I rearrange v = u + a t?

Rearranging gives these forms: to find final velocity: v = u + a t. to find initial velocity: u = v − a t. to find acceleration: a = (v − u) / t. to find time: t = (v − u) / a.

Practise final velocity questions

Include unit conversions (km, g, minutes…)

Press the button for a question with random numbers. Work it out on paper first, then type your answer.

More motion equations: Speed, distance and time, Acceleration, Velocity squared, Displacement under constant acceleration, Displacement from average velocity, Momentum, Force and change in momentum, Centripetal force. See the full list on the a-level physics equation calculator page.