Choosing the right measuring instrument
Decide which instrument to use for each measurement of length, mass, time and volume, thinking about the size of the quantity and the accuracy needed.
Core concept
The right instrument depends on the quantity, its size and the accuracy needed: a tape for metres, a vernier caliper for tenths of a millimetre, a screw gauge for hundredths
Topic: Measurement
Every measurement needs an instrument that suits the quantity, its size and how accurate the answer must be. For length, a measuring tape reads long distances to the nearest centimetre, a metre rule reads to 1 mm, a vernier caliper to 0.1 mm and a screw gauge to 0.01 mm. mass: How much matter something has, measured in grams or kilograms. It is the same everywhere. All key words is measured with a balance, time with a stopwatch, and the volume: How much space something takes up, measured in millilitres or cubic centimetres. All key words of a liquid, or of an irregular solid by displacement, with a measuring cylinder.
What you will learn
- Name the instrument used to measure length, mass, time and volume.
- Match an instrument's least count to the accuracy needed.
- Choose the best instrument for a given measurement.
Before you start
- Know the SI units of length, mass, time and volume.
Materials
- Measurement task cards
Equipment
- Measuring tape, metre rule, vernier caliper, screw gauge, balance, stopwatch, measuring cylinder
Procedure
- Choose a measurement card and check the size of the quantity and the accuracy needed.
- Place each card under the best instrument.