How_To_Be_Good_At_Math

188

Imperial units

We’ve looked at the units we use to measure things in the metric

system. In some countries, a different system is used to measure.

It’s called the imperial system, and it’s useful to be aware of the

different units that make up the system.

MEASUREMENT • IMPERIAL UNITS MEASUREMENT • IMPERIAL UNITS

The imperial system

Each unit in the imperial

system is very different

to the next, because they

have been inspired by

different things over

thousands of years.

Mass

Just as with the metric

system, there is a range of

different units we can use in

the imperial system to measure

mass, such as ounces, pounds,

and imperial tons.

The dog has a mass

of 55 pounds.

If we were weighing

the dog in metric units,

we would measure it in

kilograms. The dog has

a mass of about 25 kilograms.

In the imperial system,

we use units called

pounds to weigh things

like this dog.

Mars mix-up

In 1999, NASA made a very expensive mistake

with units. Their $125 million Mars Climate Orbiter

was lost because someone didn’t do the right

conversions! One team had been working in metric

units, while the other worked in imperial units.

As a result, the probe flew too close to Mars.

It was lost, and probably destroyed, as it entered

the planet’s atmosphere.

REAL WORLD MATHS

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