Physical Science and Measuring Systems
Physical Science – the study of the properties of matter and energy
Property – a feature or characteristic
Matter – the “stuff” things are made of…more formally…Matter is anything that has mass and volume (takes
up space)
Energy – anything not made up of atoms (matter) is energy. Energy is the ability to change matter
Some preperties of Matter – color, shape, density, texture, flexibility, smell, taste, weight, conductivity –
ability to conduct heat and malleability – ability to be bent into thin layers
2 Kinds of Properties
1. Qualitative Properties – describe qualities such as color, shape or other descriptive terms
2. Quantitative Properties – uses measurement of features or characteristics
Measurement – Using Tools
To read measurements:
1. Read the numbers – counting by ?
2. Count the spaces between them – (Not the lines)
3. Find the difference between the 2 number readings divided by the number of spaces
Example:
difference
Spaces
10 = 2
5
Measuring Systems
Measuring systems evolve over time
Beginning with Hunting-Gathering societies:
Hunters – Gatherers – people who hunted and gathered their food. They did not need to trade. They did not
need to communicate. They moved from one place to another following the food supply. They did not need a
measurement system.
Agricultural Societies
People no longer needed to travel in order to follow moving herds or depleted locations. They found out how
seed and farm for food. This allowed them to settle in one place. Then they began trading foods and materials
Measuring became necessary due to trade and the need to communicate. People needed to invent a
measuring system in order to communicate.
NOTE: In order to Trade, you need to Communicate
In order to Trade and Communicate, you needed a standard measure
Standard Measure – an amount everyone agrees with to use for comparison
Measuring Systems:
First Measuring Systems were based on body parts
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Span = distance from pinky finger to thumb with a flat palm
Hand = lengthy of 4 fingers turned sideways
Cubit – distance from elbow to middle finger
Foot = the size of your foot
Pace = a giant step
Advantages of the Body Parts System
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You always have your tools with you
Everyone can relate to it
Disadvantages of the Body Parts System
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Everyone has different size body parts
NOTE: When trade becomes more widespread, the body system doesn’t work anymore
England – has the largest navy and trades with countries all over the world
 She wanted all the countries she traded with to use her system of measurement and shw got her way
because she had the largest navy and the biggest trade
 King of England steps in and standardizes the measurements in his country
 He measures the distance from his outstretched arm to his nose and calls it a yardstick
 Then hundreds of yardsticks are made from that model
 The English System develops
The English System includes the following units (and more)
Tbs
Tsp
Ounces
Cups
pints
quart
gallons
barrel
inches
feet
yards
miles
ounces
pounds
tons
*These units are already in place – developed by people over time
The King of England took these units and standardized them
Advantages of the English System of Measurement
1. Same for everybody
2. We can all trade and communicate
Disadvantages of the English System of Measurement
1. No Pattern !
2. Too many units
3. Not reproducible – can’t make it yourself
1790’s
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- A group of scientists meet in FRANCE
They start from scratch (begin all over) and invent a system based on the size of the earth
They decided to base their measuring system on the EARTH – not body parts
Scientists already knew the size of the Earth and invented the meter
Meter = 1/10,000,000 the distance from the equator to the North Pole
(They used a shadow to determine the length of a meter – now making it reproducible)
Note – you can make your own meter stick by putting a stick in the ground and waiting a certain amount
of time and then measuring the length of its shadow – so this system is reproducible
Using the meter gave us a way to measure distance. ….but what about weight and liquid measurement?
They used meter sticks to build a box 1000cm in length, 1000 cm in width, and 1000cm in depth =
1000cm cubed
They called this liter and now we had a liquid measure
They decided that 1 liter of water = 1 kilogram – and now they had a weight
SO……
1. the meter – measures distance
2. the gram –measures mass
3. the liter –measures liquid
THIS SYSTEM WAS CALLED - LE SYSTEME INTERNATIONALE DE UNITE
We call it the SI or Metric System because it all started with the meter.
* They needed to come up with smaller and larger units and they did this by using prefixes added to the base
unit….example…KILO means 1000…so a KILOMETER = 1000 meters
Metric Base Units
Meter - measures distance ( 1 meter = 39 inches)
Gram – measures mass ( 1 g = about the mass of a paper clip)
Liter - measures liquid ( 1 L = about a quart)
Metric Prefixes
(Lets us measure item too large or small for the base units)
Kilo
Hecto
Deca
Base
Deci
Centi
Milli
1000
100
10
(one gram, meter, Liter, volt, joule, etc)
0.1
0.01
0.001
Memorize the Prefixes
K
h
da
m
d
c
m
K
I
L
O
h
e
c
t
O
d
e
c
a
b
a
s
e
d
e
c
I
c
e
n
t
I
m
i
l
l
i
Helpful Mnemonic
K
H
D
M
D
C
M
K
I
N
G
h
e
n
r
y
d
u
n
k
s
m
a
n
y
d
a
n
i
s
h
c
a
k
e
s
m
u
f
f
i
n
h
Converting the Metric System
Problem:
I need 2.5 L of acid, but I only have a 100mL graduated cylinder. How many mL is 2.5L?
2.5 L = _____________ mL
K h d m d c m
I need to go from L to mL…so I need to move my
decimal 3 places to the right.
Answer:
4 Steps for Metric Conversions
1.
2.
3.
4.
Write the prefixes in order (k h d m d c m)
Determine the direction you need to move the decimal point
Count how many units you need to move
Move the decimal point
2.5 L = 2500 mL