SI Measurements

Question 1

What is the SI (Systeme international) measurements

Answer 1

The metric system of measurement used by the majority of the world

Question 2

How do you convert measurements in the metric system with the conversion ladder?

Answer 2

There are seven steps in the conversion ladder –
Kilo (k) (biggest unit)
Hecto (h)
Deka/Deca (da)
Base – this is the base unit of what you are measuring
Deci (d)
Centi (c)
Mili (m) (smallest unit)

You count how many steps there are between the two units and you move the decimal place the number steps.

If you are moving up the ladder you move the decimal point to the left.

If you are moving down the ladder you move the decimal point to the right.

Question 3

What are some common units of measurement?

Answer 3

for mass (or weight) = grams
for volume (liquid) = litres
for distance = metres

Question 4

How do you convert units of measurment in the metric system using unit analysis?

Answer 4

There are seven steps in the conversion ladder –
Kilo (k) (biggest unit)
Hecto (h)
Deka/Deca (da)
Base – this is the base unit of what you are measuring
Deci (d)
Centi (c)
Mili (m) (smallest unit)

For each step you move up the ladder (from smaller to larger) you divide by a factor of 10 – if you move 3 steps this is 10 x 10 x 10 or 1,000 so divide by 1,000

For each step you move down the ladder from larger to smaller) you multiply by a factor of 10 – if you move 4 steps this is 10 x 10 x 10 x 10 = 10,000 so mutliply by 10,000

Question 5

1 cm = ____ mm

Answer 5

10 mm

Question 6

1 hm = ____ dm

Answer 6

1,000 dm

Question 7

1 m = _____ cm

Answer 7

100 cm

Question 8

1 km = ____ m

Answer 8

1,000 m

Question 9

What is another system of measurement call, that is used for football and in the construction industry?

Answer 9

Imperial system

Question 10

What is a referent?

Answer 10

It is something familiar used to estimate the measure of something

Question 11

What is a referent for millimeters?

Answer 11

fingernail thickness

Question 12

What is a referent for centimetres

Answer 12

width of a paper clip

Question 13

What is a referent for kilometers

Answer 13

length of 7 football fields

Question 14

What quantities can you measure with each SI unit?

a) kg
b) m
c) yr
d) L

Answer 14

a) mass
b) distance
c) time
d) volume

Question 15

What are two ways to convert units of measurement?

Answer 15

1) equivalent statements - each of the units equal the same amount
ie. 1 cm = 10 mm or 1h = 60s

2) proportional reasoning – where you write the equivalent statements as a ratio – so they always equal one
i.e. 1km/1m 12 in/1 ft 365 days/12 months

Question 16

What is a conversion factor?

Answer 16

When you muliple or divide a number by the rations made from equivalent statements (using proportional reasoning)

Question 17

What is a scale?

Answer 17

It is the relationship between distance in an image and the actual distance – ie. scale on a map might be 1 cm = 200 km

Question 18

What is a scale factor?

Answer 18

The factor by which all dimensions are enlarged or reduced – also known as the multiplier