1. The Science of Physics
Chapter One

2. What is Φΰσις” ?
Physics: from the greek word “Φΰσις” ( Physis: meaning nature
The study of all the natural sciences
Motion through spacetime
Matter
Gravity
Light
Energy
Force
Physics is the analysis of nature

3. What is Φΰσις” ? Thales: Democritus: Ptolemy: Archimedes: Pythagoras:
first to question what makes matter
Democritus:
Origin of atoms
Ptolemy:
Nature of the stars
Archimedes:
Engineering and buoyancy
Pythagoras:
Quantitative answers

4. What is Physics? Physics is the study of the physical world.
It explains how things work and why they do what they do.

5. Scientists use models to simplify things
For example: Imagine studying the motion of a sailboat from one point to another.

6. Models
Ignore things that don’t matter (color, shape, waves, wind, sounds, etc.)

7. Models
Ignore things that don’t matter (color, shape, waves, wind, sounds, etc.)
Treat the boat as a point with no shape, the water as a smooth surface, and wind blowing in only one direction

8. The Scientific Method
Imagine a police investigation of a car accident. You are the detective. How would you figure out what happened?

9. Step 1: Make observations and collect data
Step 2: Form a Hypothesis (also called an educated guess) - I think this is what happened….
Step 3: Do experiments to test your hypothesis
Step 4: Revise hypothesis, if necessary, according to experimental data
Step 5: Draw a final conclusion: “This is what happened”

10. The SI System of Measurement
(International System)
International - used to communicate results to
anyone throughout the world.
- based on powers of ten
Easy
Give him cm and he’ll take cm
Give him an inch and he’ll take a mile
(cm)

11. meter (length) meter (length) kilogram (mass) gram (mass)
The 3 Fundamental units in the SI system :
Base Units Fundamental Units
meter (length)
kilogram (mass)
second (time)
meter (length)
gram (mass)
second (time)

12. Cannot be just a number. Must have a unit with the quantity.
Measurements
Cannot be just a number. Must have a unit
with the quantity.
Dimension - Description of what kind of quantity is represented by a measurement
Three Fundamental or Basic dimensions
1. Length
2. Mass
3. Time

13. Derived Units:
Formed by combining fundamental units
with multiplication or division.
Examples: m3
m/s
kg m/s2
m/s2
(newton)

14. Merry king henry died belly up drinking chocolate malted milk mega M k
Power of 10
SI Prefixes
Merry
king
henry
died
belly up
drinking
chocolate
malted
milk
______ ____
mega M k
______ ____
kilo
______ ____
hecto h
______ ____
deka da
base unit
meter, gram, liter etc
______ ____ 1/
deci d
______ ____ 1/
centi c
______ ____ 1/
milli m
______ ____ 1/
micro m

15. SI Prefixes
______ ____
mega M k
______ ____
kilo
______ ____
hecto h da
______ ____
deka
base unit
meter, gram, liter etc
______ ____ 1/
deci d
______ ____ 1/
centi c
______ ____ 1/
milli m
______ ____ 1/
micro m

16. Conversion: chart method ( step method)
Move up the chart
one step
Move decimal to left or
Subtract 1 from exponent
kilo to mega
Count as 3 steps
micro to milli

17. Convert 1,235 g to kg

18. mega M kilo k hecto h deka da base unit 3 steps 4 steps up 1 step
Convert 2,230 hm to Mm
______ ____
mega M
______ ____
______ ____
kilo k
hecto h
______ ____
deka da
base unit
meter, gram, liter etc
3 steps
4 steps up
1 step
4 decimal places left
2,230 hm Mm

19. base unit deci d centi c milli m micro 3 steps 3 steps
Convert mg to g
6 steps up
______ ____ 1/
base unit
meter, gram, liter etc
______ ____ 1/
deci d
______ ____ 1/
centi c
milli m
micro
3 steps
______ ____ 1/
3 steps mg
6 decimal places left
5 000 g

20. mega M kilo k hecto h deka da base unit ______ ____ 1 000 000 106
Convert 1.5 x 108 m to km
______ ____
mega M
______ ____
______ ____
kilo k
hecto h
______ ____
deka da
base unit
meter, gram, liter etc
3 steps up
1 .5 x 108 m
Subtract 3 from exponent
1.5x105 km

22. Convert Mg to dag

23. Convert 54,800 L to mL
Convert Mg to dag
Convert m to km
Convert 5,000, mg to g
Convert 2,230 hm to Mm
Convert 2,230 hm to Mm
Convert 2,230 hm to Mm
Convert 2,230 hm to Mm