measuring Mass

​Measuring Mass

We measure mass when we want to find the weight of an item. A scale is the instrument used to weigh items. The scale maybe a spring or balanced.

​BALANCE SCALE

​SPRING SCALES

Multiple Choice

What instrument is used to measure mass?

• tape measure

• yard stick

• scale

• measuring cup

The gram is the basic unit of mass. This is a very small unit so the kilogram has become the standard unit of mass.

The kilogram (kg), the gram (g) and the milligram (mg) are the only unit s used for practical purposes. A further unit is used for large masses, the tonne (t).

1 tonne = 1000 kg

1 kg = 1000 g

1 g = 1000 mg

Multiple Choice

What is the standard unit of measuring mass?

• gram

• centigram

• kilogram

• tonne

Multiple Choice

How many grams are in a kilogram?

• 100

• 1,000

• 10

• 10.000

Multiple Choice

Which of the following units is used to measure very heavy items?

• centigram

• gram

• tonne

• kilogram

​MASS	​ABBREVIATION	​RELATIONSHIP TO BASIC UNIT
​1 kilogram	​1 kg	​1000 g
​1 hectogram	​1 hg	​100 g
​1 decagram	​1 dag	​10 g
​1 gram	​1 g	​1 g
​1 decigram	​1 dg	​0.1 g
​1 centigram	​1 cg	​0.001 g
​1 milligram	​1 mg	​0.0001 g

​The relationship between the different units of mass is shown in the table below.

Multiple Choice

Which of the following unit is bigger kilogram or gram? ______

• gram

• kilogram

CONVERTING UNITS OF MASS

When converting from a small to a large unit we divide. When converting from a large to a small unit, we multiply.

So if 1000 g = 1 kg, then 3000 g = 3 kg . We divide 3000 by 1000 to get the answer 3.

7546 g = ? kg We should divide 7546 by 1000 to get 7.546 kg

1.789 kg = ? g We should multiply 1.789 by 1000 to get 1789 g

Multiple Choice

True or false. 0.25 kilogram is the same as 250 grams. ________

• True

• False

Multiple Choice

When we are converting from a smaller to a larger unit, should we divide or  multiply?  _________

• divide

• multiply

Multiple Choice

What is the total weight  in kilograms of all the items below? 

                                                   

   625 g                                 1447 g                                  1360 g

• 3.567 kg

• 3.234 kg

• 3.442 kg

• 3.432 kg