Teach Genie
Teach it back in your own words, spot gaps, and remember it better.
The word "per" means divide. So average speed is distance per time, and density is mass per volume.
You must also match the units. Speed is often in m/s\text{m/s}m/s or mph, while density might be in g/cm3\text{g/cm}^3g/cm3 or kg/m3\text{kg/m}^3kg/m3.
The key formulas are below. Pressure has the same divide pattern, even though today we will focus on speed and density.
average speed=distancetime \text{average speed} = \frac{\text{distance}}{\text{time}} average speed=timedistance density=massvolume \text{density} = \frac{\text{mass}}{\text{volume}} density=volumemass pressure=forcearea \text{pressure} = \frac{\text{force}}{\text{area}} pressure=areaforceQuestion 1
2 marksA sprinter runs a distance of 200 metres in 25 seconds.
Work out the average speed of the sprinter.
In a rate like miles per hour, what operation does per signal?
Revision notes for Edexcel GCSE Maths Speed and Density. Open the guide for explanations and worked examples. Written against the Edexcel GCSE Maths (1MA1) specification, so the content matches what's examinable rather than general Maths background.
1 of 5
A cyclist travels 45 miles in 3 hours. What is the cyclist's average speed?
