Transcript Scientific Measurement

Scientific Measurement
• In the late 1700s the French Academy of
Sciences began to form a global measurement
system now known as the International
System of Units or SI
• Sometimes we call it the Metric System
• Scientists and most of the world use this
system of measurement
• Advantages of SI units/Metric System
– Helps scientists share and compare observations
and results
– Based on the number 10 so converting units is
easy
Let’s look at the chart of common SI Units and
Conversions on page 24.
Area is a measure of the size of a surface or
region. Units are squared.
Area = Length x width
5cm
5 cm x 4 cm = 20 cm2
4cm
• What tools do we use to measure area?
• Which units are area based on?
Volume is a measure of the size of a body or
region in 3 dimensional space.
Or more simply stated …
Volume is a measure of how much space an
object takes up.
Which units describe volume? Liters
How do you find the volume of a regular
shaped object like a box?
Multiply its length by its width by its height.
Volume = Length x width x height
5 cm
5 cm
5 cm
5cm x 5cm x 5cm = 125cm3
Wait a minute!!! Two slides ago you told us the
units of volume were liters.
How can the volume of the ice cube be 125 cm3?
Liters are based on the meter. A cubic meter( 1m3) is
equal to 1000L. So 1000L will fit into a box measuring 1 m
on each side. So 1L = 1m3 and 1mL = 1cm3
125 cm3 = 125 mL
How do you find the volume of an irregular shaped
object?
Measure the volume of liquid the object displaces.
Look at example on page 25
What tools do scientists use to measure volume?
Graduated Cylinders
Mass is a measure of the amount of matter in an
object.
Measured in the base unit of grams.
Larger objects will be measured in Kilograms (Kg)
while smaller objects will be measured in milligrams
(mg)
Mass is measured by using a balance. We will use a
triple beam balance
Temperature is a measure of how hot or cold something is.
The SI units of temperature are Kelvin (K) however many
scientists use Celsius(oC)
The tool used to measure temperature is the thermometer.
Converting SI Units
• King Herod’s Daughter Usually drinks chocolate milk
Meters
Liters
grams
Let’s convert 500 mL to L.
56.9 cm to m
.15379kg to g