MATHEMATICS Measures – Units, Equipment and Scales

Lesson Objectives The aim of this powerpoint is to help you… Determine the appropriate ‘units’ to measure in, for length, mass & capacity Determine the appropriate equipment to use to measure something Work out how to interpret different scales

Appropriate measures & equipment Given a particular situation you need to decide on two things… What units are most appropriate to use to measure in What is an appropriate measuring device

What do we measure? LENGTH or distance i.e. How long something is. MASS (sometimes called ‘weight’ by mistake) i.e. How heavy something is. CAPACITY (sometimes called ‘volume’) i.e. How much liquid is contained.

Metric Units for Length LENGTH Millimetre [mm] (for very small or thin distances) Centimetre [cm] (for short distances up to 2 metres) Metre [m] (for distances up to 2 kilometres) Kilometre [km] (for longer distances between places) Examples of measuring devices for length are… Rulers, Trundle Wheels, Pedometers, Milometers…

Metric Units for Mass MASS Milligram [mg] (for very light weights, e.g. feather) Gram [g] (for very small objects, e.g. a coin) Kilogram [kg] (for heavier weights, e.g. a person) Tonne [T] (for very large, heavy objects, e.g. car) Examples of measuring devices for mass are… Kitchen scales, bathroom scales, weighbridges…

Metric Units for Capacity CAPACITY Millilitre [ml] (for most small vessels, e.g. spoon) Centilitre [cl] (also for small containers, e.g. bottle) Litre [l] (for larger vessels, e.g. petrol tank) Examples of measuring devices for capacity are Syringes, pipettes, measuring jugs, petrol pumps, teaspoons, tablespoons…

Sample Situation 1 You wish to measure the time it takes you to walk home from school (a distance of about 1.5 miles)… measures & devices? It should take you a time in MINUTES A WRISTWATCH would be a suitable device (as opposed to a wall clock or a stopwatch)

Sample Situation 2 You wish to measure the thickness of a strand of copper wire…measures & devices? It should be a length in MILLIMETRES (or more likely a fraction of a millimetre) A MICROMETER would be a suitable device (rather than a ruler or tape measure)

SCALES When measuring, you need to consider the scale of each larger marking and therefore the value of each smaller marking You divide the difference between larger markings by the number of smaller sections there are between them Let’s look at 3 examples…

Example 1 The difference between 3 and 4 is 1. Divide this by 10 (smaller sections) and each smaller marking is worth 1 ÷ 10 = 0.1 The arrow is pointing at 3 + (4×0.1) =

Example 2 The difference between 3.5 and 4 is 0.5 Divide this by 10 (smaller sections) and each smaller marking is worth 0.5 ÷ 10 = 0.05 The arrow is pointing at (6×0.05) =

Example 3 The difference between 9.1 and 9.2 is 0.1 Divide this by 5 (smaller sections) and each smaller marking is worth 0.1 ÷ 5 = 0.02 The arrow is pointing at (4×0.02) =

What next? Print out the notes called Meas1. Read through them and make sure you answer any questions. Work through the following MyMaths lessons: Units of Length: Units of Mass: Units of Capacity: Save and complete the worksheets: Meas-S1.xlsx & Scales-S1.xlsx Now move on to the Meas2a powerpoint