Difference between speed and velocity?

Speed is the magnitude of velocity; velocity is a vector.

Average speed formula?

\frac{total distance}{total time}

Horizontal line on a velocity--time graph?

Constant velocity, zero acceleration.

Which quantities can be negative?

Position, displacement, velocity and acceleration; not distance or speed.

How find distance if the velocity--time graph goes below the axis?

Add the magnitudes of the areas above and below.

Can distance be less than the magnitude of displacement?

No; distance is at least as large.

Language of kinematics and motion graphsEdexcel A-Level Maths: Flashcards

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Difference between distance and displacement?

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Difference between distance and displacement?: Distance is total path length (positive); displacement is change in position with direction.
Difference between speed and velocity?: Speed is the magnitude of velocity; velocity is a vector.
Average speed formula?: $\frac{\text{total distance}}{\text{total time}}$
Average velocity formula?: $\frac{\text{displacement}}{\text{time}}$
Gradient of a displacement--time graph?: Velocity.
Gradient of a velocity--time graph?: Acceleration.
Area under a velocity--time graph?: Displacement.
Horizontal line on a displacement--time graph?: The object is at rest.
Horizontal line on a velocity--time graph?: Constant velocity, zero acceleration.
Which quantities can be negative?: Position, displacement, velocity and acceleration; not distance or speed.
How find distance if the velocity--time graph goes below the axis?: Add the magnitudes of the areas above and below.
Area of a trapezium?: $\frac12(a+b)h$
Can distance be less than the magnitude of displacement?: No; distance is at least as large.

Exam questions on Language of kinematics and motion graphs

A runner jogs 300 m east from a point $O$ in 100 s, then turns and jogs 100 m west in 50 s, all in a straight line. Take east as the positive direction.
Find the average speed for the whole run, and explain why it is not equal to the magnitude of the average velocity.2 marks
A train moves along a straight track. Its velocity increases uniformly from $0$ to $20$ m s $^{-1}$ in 10 s, stays constant at $20$ m s $^{-1}$ for 30 s, then decreases uniformly to rest in 20 s. Consider its velocity--time graph.
Find the average speed of the train over the whole journey.2 marks
A particle $P$ moves on a straight line through a fixed point $O$ . Its displacement from $O$ is $s$ metres at time $t$ seconds. At $t=0$ , $s=2$ . From $t=0$ to $t=4$ , $P$ moves with constant velocity to $s=14$ . From $t=4$ to $t=7$ , $P$ is at rest. From $t=7$ to $t=12$ , $P$ moves with constant velocity to $s=-6$ .
Find the velocity of $P$ in each of the three stages of its motion.3 marks

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Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).