Measurement in Science
 When
scientists carry out experiments, they need
to report exactly what they have done. Scientists
needed a standardized measuring system that all
scientists across the world could use. It has been
agreed that everyone could should use SI units.
Common Measurements in Science
1. Length:
Length is the distance between two points. The
units for length are the meter (m), centimeter (cm) and
millimeter (mm). Scientists use a meter rule to measure
length.
2. Mass:
Mass is the amount of matter in an object. The units
for mass are gram (g) and kilogram (kg). Scientists use
triple beam balances to measure mass.
Common Measurements in Science
3. Volume:
Volume is the amount of space taken up by an
object. The units for volume are cubic centimeter (m3) or
milliliters (ml) and cubic meters (m3). Scientists use
measuring cylinders to measure the volume of liquids.
4. Time:
Time is the measurement of how long an event
takes place for. The units for time are seconds (s), minutes
(min) and hours (h). Scientists use stopwatches to measure
time.
Common Measurements in Science
5. Temperature:
Temperature is a measure of the amount of
heat energy in a substance. The unit for temperature is
degrees Celsius (˚C). Scientists use thermometers to
measure temperature.
Why do Scientists Measure?
 How
heavy is a bus?
 How
long is the ABC Highway?
 How
much space is inside an aquarium?
 How
long does it take to ride home from school?
 How
hot is the water in the bathtub?
You may be able to make a guess, but you will probably not
be exactly right.
Why do Scientists Measure?
 Scientists
measure so that
they can know exact values.
 We
will focus on measuring
five quantities: time, mass,
temperature, volume and
length.
Why do Scientists Measure?
 How
heavy is a bus? Mass
 How
long is the ABC Highway? Length
 How
much space is inside an aquarium? Volume
 How
long does it take to ride home from school? Time
 How
hot is the water in the bathtub? Temperature
We measure using standard units of length
Millimetres (mm)
Centimetres (cm)
Kilometres (km)
Metres (m)
Comparing Units of Length
1
mm = 0.1 cm
 10
1
mm = 1 cm
cm = 0.01 m
 100
1
cm = 1 m
m = 0.001 km
 1000
m = 1 km
Remember
Two sides of a Ruler
 There
 In
are two sides to a ruler: centimeters and inches
science you will NEVER EVER use the inches side!
 The
smaller/shorter dashes with NO numbers represent
millimeters “mm”
 The
longer dashes with numbers represent centimeters
“cm”
Finding the Length
1. Find
2. Use
the two numbers that the line/object is between.
the smaller of the two numbers. This is the first part of
your answer.
3. Now
count the dashes after the lower number. This is the
second part of your answer
4. Take
both parts of your answer and put a decimal between
the two numbers
5. Label
your answer with the unit centimeters or “cm”
1. The screw is between 5 and 6
2. I will use the 5 since it is smaller
3. I count 1 dash after the big number
4. Answer: 5.1 centimeters
1. The line is between 3 and 4
2. I will use the 3 since it is smaller
3. I count 4 dashes after the big number
4. Answer: 3.4 centimeters
1. The line is between _____ and ______
2. I will use the _________ since it is smaller
3. I count ____ dashes after the big number
4. Answer: _______._______ centimeters
1. The line is between 11 and 12
2. I will use the 11 since it is smaller
3. I count 6 dashes after the big number
4. Answer: 11.6 centimeters
1. The line is between _________ and _________
2. I will use the _________ since it is smaller
3. I count _____________ dashes after the big number
4. Answer: _______._______ centimeters
1. The line is between 1 and 2
2. I will use the 1 since it is smaller
3. I count 8 dashes after the big number
4. Answer: 1.8 centimeters