GCSE · Compound units & rates

Converting compound units and rates of flowExam-style questions

Why converting a compound unit means converting both of its parts, where the ÷3.6 between km/h and m/s comes from, why g/cm³ to kg/m³ is ×1000, and how rates of flow work.

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13 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try

DifficultyAll Level 2 Level 3 Level 4 Level 5

1
The density of a liquid is 1.05 g/cm³. Convert this density into kg/m³.
Level 4 · 3 marksTry it
2
A car travels at 90 km/h. A cheetah runs at 27 m/s.

Which is faster, and by how many m/s? You must show your working.
Level 4 · 3 marksTry it
3
Water flows through a pipe at a constant rate of 0.3 litres per second, into an empty tank with a capacity of 0.72 m³.

Given that 1 m³ = 1000 litres, work out how many minutes it takes to fill the tank.
Level 4 · 4 marksTry it
4
A car uses petrol at a rate of $6.2$ litres per $100$ km.

Petrol costs £ $1.45$ per litre.

(a) Work out how many litres of petrol the car uses on a journey of $350$ km.

(b) Work out the cost of the petrol for the journey.
Level 4 · 4 marksTry it