The density of a substance is measured as the substance's mass per unit of volume.

The mass of a substance is a measure of the quantity of matter in the substance.

Compound measures for density

Maths

Checking and further securing understanding of direct proportion in context

Compound measures for speed

Compound measures for pressure

Converting between metric speed measures

Converting between metric and imperial speed measures

Combining speeds

Combining densities

Problem solving with compound measures

In this unit, pupils will be exploring the multiplicative relationship between different compound measures. Ratio will be one of the ways in which this is explored and the skills from the prior unit will aid understanding. There are also links to the volume units as volume is required for the density formula.

In this unit, pupils explore the multiplicative relationship between different compound meaures and units such as speed, rates of pay, density and pressure.

Compound measures

The density of a substance is measured as the substance's mass per unit of {{ }}.

The volume of an object is 150 $$cm^3$$ and has a mass of 375 g. The density of the object is {{ }} $$g/cm^3$$.

The density of an object is 120 $$g/cm^3$$, the mass of the object is 750 g. The volume of the object is {{ }} $$cm^3$$.

The density of an object is 12.8 $$g/cm^3$$, the volume of the object is 24.5 $$cm^3$$. Calculate the mass of the object. (Give your answer in grams).

The density of this cuboid is 3.6 $$g/cm^3$$. Calculate the mass of the cuboid. (Give your answer in grams).

Pace is the rate of movement.  It is measured as the time taken per unit of {{ }}.

A car travels 12 miles in 15 minutes what is its average speed?  Make sure you include the unit with your answer.

Match each scenario with the correct speed.

Calculate the speed during the last part of the journey. Remember to include the units of your answer.

The average speed of a helicopter is 160 mph. How far can it travel in 1 hour 15 minutes?

The distance from London to Athens is approximately 1500 miles.  If a helicopter travels at an average speed of 160 mph. How long will the journey take?  Give your answer as an exact answer in hours.

Compound measures for density

Lesson outcome