Transcript The Metric System

The Metric System
How do we measure things
in science?
Length
(measures the distance from one
point to another)
• Base Unit
–Meter
• Tool
– Meter stick/ruler
Meter sticks
This lizard is 3 meters long!
(a meter is about 39 inches)
Volume
(measures the amount of space an
object takes up )
• Base Unit
–Liter
• (liquids)
–Cubic
centimeters
• (solids)
• Tool
– Graduated
Cylinder (liquids)
– Ruler (solids)
Graduated Cylinders
Measure the volume of liquids
Three steps to reading a graduated
cylinder
1. Place the graduated cylinder on
level surface
2. Read at eye level
3. Read from the bottom of the
meniscus
Measuring volume of a solid
This solid is three cubic meters in
volume. L x W x H = volume
Formula for finding the volume of a
rectangular solid
Length x Width x Height
L x W x H
Finding the volume of an irregular
object
1. Place enough water in a graduated
cylinder to cover the object. Record
the volume.
2. Add the object and record the new
volume.
3. Find the difference between the two
volumes and that is the volume of
the irregular object.
Mass
(measures the amount of matter in
an object)
• Base Unit
–gram
• Tool
–Electric
balance
Electronic balance used to
measure mass
Steps before using a balance
1.Clean the weigh pan
2.Tare the balance (zero it
out)
This stuff is supposed to give you
more muscle mass
Temperature
(measures heat and chill)
• Base Unit
–Degrees
celcius
• Tool
–Thermometer
Both Celsius and Farenheit scales are seen
here. In science we do not use degrees
Farenheit.
This man is in a freezing cold environment
as can be seen by his frozen hair and
beard. He is sitting in a natural hot spring
that is very warm at the same time!
Density
• How closely the molecules of an object are
packed together.
• Density can be calculated if the mass and
volume are known
• Density = mass divided by volume
Measuring density using an electric
balance for mass and a graduated cylinder
for volume.
Less dense liquids
float on more dense liquids in this density column
Weight of an object
• The mass of an object multiplied by
the force of gravity.
• Weight changes if gravity changes.
(like on the moon)
• Mass does not change on the moon.
Your weight will be less on the
moon, but your mass does not
change