Transcript Metric System Basics

Metric System
Types of Measurements
• Length-measure of distance
– Measured with a meter stick or ruler
• Volume-measure of how much
space an object takes up
– Measured with a graduated
cylinder, by water displacement, or
by equation
• cube volume=length X width X height
(LXWXH)
• Mass-technically a measure of
matter, but here on Earth it is the
same thing as weight
– Measured with a triple-beambalance
Metric System
• The metric system is based
on a base unit for each
measurement
• Length = meter
• Volume = liter
• Mass(Weight) = gram
• Temperature = Celsius
• Time = seconds
• Prefixes plus base units
make up the metric system
– Example:
• Centi + meter = Centimeter
Metric System
• The three prefixes that we will use
the most are:
– kilo
– centi
– milli
Base Units
kilo
hecto
deka
meter
gram
liter
deci
centi
milli
Metric System
• These prefixes are based on powers
of 10.
• From each “step” is either:
• 10 times larger
or
• 10 times smaller
Base Units
kilo
hecto
deca
meter
gram
liter
deci
centi
milli
Why 10 times larger?
– Units that are 10 times larger
or smaller are easier to
convert.
1 centimeter = 10 millimeters
40
1 mm
41
1 mm
1 mm
1 mm
1 mm
1 mm
40
1 mm
1 mm
1 mm
1 mm
41
1 cm
Metric System
• For each “step” to right,
you are multiplying by 10
1 liter = 10 deciliters = 100 centiliters
( 1 x 10 = 10)
=
(10 x 10 = 100)
2 grams = 20 decigrams = 200 centigrams
(2 x 10 = 20)
kilo
hecto
deca
meter
liter
gram
=
(20 x 10 = 200)
deci
centi
milli
Metric System
• An easy way to move within the metric
system is by moving the decimal point one
place for each “step”
1 meter = 10 decimeters = 100 centimeters
or
1.00 meter = 10.0 decimeters = 100. centimeters
kilo
hecto
deca
meter
liter
gram
deci
centi
milli
Metric System
• Now let’s try from meters to kilometers:
1600 meters =
160 decameters
16 hectometers
1.6 kilometers
kilo
hecto
deca
meter
liter
gram
deci
centi
milli
Metric System
• If you move to the left in the diagram,
move the decimal to the left
• If you move to the right in the diagram,
move the decimal to the right
kilo
hecto
deca
meter
liter
gram
deci
centi
milli
Clicker Question
• How many milliliters are in a 2 liter
bottle of soda?
A. 0.002
B. 200
C. 2000
D. 20
kilo
hecto
deca
meter
liter
gram
deci
centi
milli
Clicker Question
• How many kilometers do they run in
a 1600 meter relay?
A. 160,000
B. 160
C. 16
D. 1.6
kilo
hecto
deca
meter
liter
gram
deci
centi
milli
Temperature
• Celsius Scale is based on water
– The freezing point of water is 0OC
– The boiling point of water is 100OC
Temperature Conversion
• The equations to convert between
Fahrenheit and Celsius are:
°F = (1.8 x °C) +32
°C = (°F-32) x 0.555
Example
• If it is 80°F outside, what is the
temperature in °C?
°C = (°F-32) x 0.555
°C = (80-32) x 0.555
°C = (48) x 0.555
°C = 26.6
Clicker Question
• If a substance is 80°C, what is the
temperature in °F?
°F = (1.8 x °C) +32
A.114
°F = (1.8 X 80) + 32
B. 176
°F = (144) + 32
C.4608
°F
= 176
D.112
Density
• Density is calculated by dividing the mass
of an object by the volume.
Density = Mass/Volume
• For example 1mL of water has a mass of
1g.
Density = Mass/Volume
Density = 1g/1mL
Density = 1g/mL
• Objects with a density less than 1g/mL will
float in water and objects with a density
greater than 1g/mL will sink in water
Clicker Question
• What is the density of a box with a
mass of 40 g and a volume of 50 mL
A. 0.8 g/mL
D = mass/volume
B.= 12.5
D
40g / g/mL
50 mL
C.= 90
g/mL
D
0.8 g/mL
D. Impossible
to Calculate
Clicker Question
• What units would you use to
measure the mass of your neighbor?
A. g
B. m
C. L
D. kg
Clicker Question
• What units would you use to
measure the length of your pencil?
A. m
B. g
C. km
D. cm