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Measuring using Instruments

Measuring using Instruments

Instruments are used to read a range of measurements such as length, weight, volume and temperature.

The important points to note when reading from dials are:

which way round to read the dial: clockwise/anticlockwise, left/right or up/down

determine the scale: what are the major and minor values

confirm what the dial is reading eg feet or metres.

Example 1

A submarine depth gauge is shown. What is the depth to the keel?

Submarine depth gauge

Read to the 40, then read the additional 7 small marks for 47.

The gauge is read in metres, so the distance is 47 metres.

Answer: 47 metres

Example 2

What is the reading on the gauge, below?

Submarine temperature gauge

Find the scale is going up in value as you read left to right.

Reading from zero and going left (and decreasing) is 4 steps, which gives -4.

The gauge is reading a temperature in degrees Celsius.

Answer: -4 ℃