
Define Independent and Dependent
Variables.
 Make up your own example.

What is a theory?

How is a theory different from a hypothesis?
The Metric System
AKA SI or Système International



When people first started to measure things,
the systems were different in different parts
of the world.
Many systems were based on parts of the
body.
Foot
Inch
Many countries tried to make a system of
measurement.
 Both France and England came up with
systems that are used today.
 England started the English Standard System
and France started the Metric
System.

English Standard
System
 Based on:
2, 3, 4, 8, 16
 Generally uses
fractions

2 pints in a quart
3 feet in a yard
4 quarts in a gallon
12 inches in a foot
16 ounces in a pound



Metric System
Based on: 10 (like
U.S. money)
Generally uses
decimals
100 centimeters in a meter
1000 grams in a kilogram
1000 milliliters in a liter

Over 95% of the world uses the Metric System.

The metric or SI (scientific international) system is
aids scientists in sharing measurements
 No need to convert another person’s data if we all work in
SI
 Ex/ NASA still works in imperial units and has had
difficulty when needing to work with other groups that
use metric
▪ In 1999 the Mars Climate Orbiter was lost because the altitude
control system used imperial units and the navigation software
used metric.

Units can be scaled by factors of 10
depending on what you are measuring
 So it can be used for small stuff as well as
large


Kilo- Hecto- Deca- Base- Deci- Centi- Milli1000 100
10
1 1/10th 1/100th 1/1000th

You are only responsible for the units in black



Measurement: Mass
Unit used: Gram (g)
Tool Used: Balance
A paper clip has the mass of about 1 gram.



Measurement: length/distance
Unit used: Meter (m)
Tool Used: Ruler/meter stick
A centimeter is about the width of a small fingernail



Measurement: Volume
Unit used: Liter (l)
Tool Used: graduated cylinder
little
1
pints)
A liter is just a
bit more than
quart (or 2





Measurement: Temperature
Unit used: Celsius (C)
Tool Used: Thermometer
0o Celsius= freezing
100o Celsius= boiling


As of the late 1970s, only the United States,
Liberia (Africa) and Myanmar (formerly
Burma in Asia) use the English Standard
System.
Every other country, and scientists
worldwide, use the metric system.


Convert 15 grams (g) to kilograms (kg)
15 g X 1 kg = .015kg
1000 g

What are the metric prefixes which we
remember with
king Henry Died by drinking Chocolate Milk

What percentage of the world’s countries use
metric?