Warmup
X
Y
-4
.039
-2
-0.32
0
-1.10
2
-1.58
4
-2.45
6
-3.02
8
-3.65
10
-4.32
12
-4.97
14
-5.66
Please complete a scatterplot for the data.
Warmup
From test corrections on the original gravity test or from reviewing relevant
chapters for vocabulary and concepts, what questions do you have before the
retake?
Finals Review Plan
Monday
Tuesday
May 21
Circular Motion
Wednesday
Thursday
May 23
Investigation and
Experimentation
May 25
Forces
Energy and
Momentum
Linear Motion
June 4
Final Exam
June 5
Rocket Lab
Friday
May 30
(HS Field Trip)
May 31
Thermodynamics
June 1
(MS Field Trip)
Linear Motion
Waves
Electricity and
Magnetism
June 5
Rocket Lab
June 6
Rocket Lab
Scientific Outcomes
Hypothesis – A testable statement which shows a cause and effect
relationship. “If _, then _,” or “_ because _.”
ex: the existence of the graviton as a force-mediating particle
Law – A clearly defined mathematical relationship which describes a natural
phenomenon and has significant evidence to support it. It has predictive
value.
ex: Universal Law of Gravitation, F = -G m m /r2
Theory – A statement which explains why and how things occur, and is often
related to a Law or Model. It has predictive value, and significant evidence to
support it.
ex: General Theory of Relativity (Gravity curves space-time)
Scientific Method Basics
Independent variable – the cause – we change it around
ex: How much we make the spider move.
Dependent variable – the effect – we measure what happens
ex: The percent chance my cat will eat it.
Controlled variables – everything else stays the same.
ex: Object size, object appearance, object smell, time of day
hungriness of cat, room lighting, how long the cat sees it.
Do people who watch too much tv really have mushy
brains?
Identify the dependent variable.
1.
2.
3.
4.
age of subject
TV amount
mushiness of brains
commercial break
frequency
5. zombie appetite
6. none of the above
0%
0%
1
2
0%
0%
0%
0%
3
4
5
6
If you eat more chocolate, then you will get
more acne.
1.
2.
3.
4.
5.
IV: Acne
DV: Chocolate
IV: Age, Chocolate DV: Gender
IV: Chocolate
DV: Acne
IV: Hormones
DV: Teens
IV: Oils
DV: Acne
Treatment, Facewashing, Sun exposure
6. None of the above
0%
1
0%
2
CV: Age, Gender
CV: Acne
CV: Age, Gender
CV: ProActiv Cream
CV: Age, Gender,
0%
3
0%
4
0%
5
0%
6
How many mealworms does it take to make Zuldjian stink up
the room a day later?
Identify the Independent Variable.
1.
2.
3.
4.
5.
6.
Mealworms
Heat
Time delay
Stink
All of the above
None of the above
0%
0%
1
2
0%
0%
0%
0%
3
4
5
6
Scientific Method Procedure Elements
Baseline – A set of measurements taken before the IV is applied, to understand the
normal value for future comparison.
ex: Mike got 5 headaches a month before he started taking medicine
Control Group – A group which does not receive the IV, for comparison during the
experiment. Identifies the presence of environmental factors.
ex: …but the people who weren’t getting medicine also got better in July.
Placebo – Fools researchers, test subjects, or both to eliminate or reveal sources of
bias.
ex: The coke/pepsi tasters didn’t know the labels were switched.
Reversal – Return to baseline, to help prove cause-and-effect.
ex: When the old tires were put back on, Jimmy once again crashed.
Before dropping any eggs onto different pillows, Joe first
dropped an egg directly onto the concrete and measured the
splatter radius. This is a:
1.
2.
3.
4.
5.
Baseline
Control group
Placebo
Reversal
More than one
option
0%
1
0%
0%
2
3
0%
0%
4
5
A baseball player claimed his home run rate was skill and not his
special ‘training regimen’. Later, when he was forced by a
Congressional committee to stop the regimen, his home run rate
dropped. This is an effective example of a:
1.
2.
3.
4.
5.
Baseline
Control group
Placebo
Reversal
More than one
option
0%
1
0%
0%
2
3
0%
0%
4
5
Data Analysis
Multiple Trials – Repeating a measurement using the same independent
variable.
ex: Sonia grew three plants with 1 cup of water, three with 2 cups…
Precision (using Standard Deviation) – A small margin of this type demonstrates
consistency, meaning low random error.
ex: By being very careful, data from Joe’s second and third trials
matched his first trial with minimal deviation.
Accuracy – A small margin of this type demonstrates an overall value close to the
correct value, meaning low systematic error.
ex: Low accuracy occurred as a result of an un-calibrated scale. The
overall answer was 5g too high.
Best-fit lines, equations, and error bars – Helpful analytic tools for use with
scatterplots.
What could you say about the accuracy and precision of
the following data, where the accepted value is 4.3:
(6.0, 6.1, 5.9, 5.8, 6.2)
1. Precision: ±.2
Accuracy: ±3
2. Precision: ±.2
Accuracy: ±1.7
3. Precision: ±.5
Accuracy: ±2
4. Precision: ±.2
Accuracy: ±1.5
0%
1
0%
2
0%
3
0%
4
What could you say about the accuracy and precision of
the following data, where the accepted value is 9.0:
(9.8, 8.1, 9.1, 8.7, 9.3)
1. Precision: ±.2
Accuracy: ±0
2. Precision: ±.9
Accuracy: ±1
3. Precision: ±.9
Accuracy: ±0
4. Precision: ±0
Accuracy: ±.9
0%
1
0%
2
0%
3
0%
4
Linear Motion
Velocity
Speed
Distance
Displacement
Acceleration
Scalar
Vector
Vector: Graphical Representation
The way to draw a vector is a line with a certain length, in a certain direction,
with an arrow to show which way it faces.
Ex:
How would you add these vectors?
2 m/s right
5 m/s left
1.
2.
3.
4.
5.
6.
7.
8.
7 m/s right
7 m/s left
5 m/s right
5 m/s left
3 m/s right
3 m/s left
2 m/s right
2 m/s left
0%
0%
0%
0%
0%
0%
0%
0%
1
2
3
4
5
6
7
8
Which answer choices describes a 4
mile distance?
1. 10 mi East, 6 mi
West
2. 20 mi North, 17 mi
South, 1 mi East
3. 2 mi East, 2 mi West
4. 5 mi East, 1 mi West
0%
1
0%
2
0%
3
0%
4
Which of these numbers is a speed?
1.
2.
3.
4.
5.
6.
15 meters
22 meters/second
25 m/s2
10 miles
10 miles/hour
10 mph/s
0%
0%
1
2
0%
0%
0%
0%
3
4
5
6
Practice Problems
1) v0=10 m/s
a=-2 m/s2
t= 4 s
v= ? m/s
2) v0=1 m/s
a=0 m/s2
t= 10 s
v= ? m/s
3) d0=100 m
v0= 10 m/s
a= -10m/s2
t= 2 s
d=? m
4) d0=0 m
v0= 0 m/s
a= 2 m/s2
t= 5 s
d=? m
Givens:
Equation:
Plug-in:
Math:
Answer:
Practice Problems
5) A car is initially stopped. The driver pushes on the gas pedal and it begins to
accelerate. After 5 seconds, it is travelling at 60mph. What was the average rate
of acceleration?
6) Acceleration due to gravity is 10 m/s2 near the surface of the Earth. If you were
to jump out of an airplane, after 1 second what would your velocity be? After 2
seconds? After 10 seconds?
Givens:
Equation:
Plug-in:
Math:
Answer:
Practice Problems
7) A rabbit has a speed of 5 m/s, and has a 100m head-start. A dog has a
constant speed of 6 m/s in the same direction. Will the dog be able to catch the
rabbit in 10 seconds?
8) A trip to Los Angeles is about 600 miles. A car averages 60 mph. A plane
averages 400 mph. A high-speed rail averages 80 mph. How long does it take
each of these modes of transportation to complete the trip?
Givens:
Equation:
Plug-in:
Math:
Answer:
Practice Problems
9) If a runner travels 400m in 60 seconds around a circular track (one lap), what is their
average speed and velocity? If a cheetah travels the same distance in 20 seconds, what
is their average speed and velocity?
10) A person ties a string to a can of water and swings it at a constant speed in a circle.
Describe the acceleration the can is experiencing in as much detail as possible. (Not a
math problem)
Givens:
Equation:
Plug-in:
Math:
Answer:
Practice Problem
11) One train leaves travelling at an average velocity of 60mph East, and another one
leaves travelling 30mph West. After 2.5 hours, what is their displacement in relation
to the station? What is their displacement in relation to each other?
12) A hang glider descends a total of 150m and then climbs back up 50m. It takes a
total of 25 seconds to do this. In m/s, what is the average speed? What is the
average velocity?
Givens:
Equation:
Plug-in:
Math:
Answer:
Practice Problems
13) A hero is rocket-packing towards a closing door at a speed of 20 m/s. The
door is 200 m away and will close in 5 seconds. Does the hero make it through?
Algebra II
13b) What is the minimum acceleration the hero should use to make it through
successfully?
Givens:
Equation:
Plug-in:
Math:
Answer:
Side-by-Side Comparison
d
d = constant
d
v = constant
d
Linear
Constant
t
v
Zero
t
a
Zero
t
t
v
Constant
t
a
Non-Linear
t
v
a = constant
Zero
t
Linear
a
Constant
t
t
Practice Problems
v
t
For the graph above, draw the equivalent displacement and acceleration
graphs (assuming it starts at d0 = 0).
Solution
d
v
t
t
a
t
Energy, Work, and Power
Energy is the ability to cause change, and is measured in Joules (J).
Law of Conservation of Energy - Energy can be transferred from object to object,
and can change form, but never just disappears.
Kinetic Energy – Large-scale motion. (Joules)
KE = ½ m v2
Potential Energy – Based on position and a force. (Joules)
PE = m g h
Work – A transfer of one kind of energy to another. (Joules)
W=Fd
Power – How quickly the work is done. (Watts)
P = W/t
Momentum and Impulse
p = m*v
∆p = F*t
Conservation of momentum: the total momentum of the system is the same, both
before and after any event.
Elastic collisions: objects bounce perfectly
Inelastic collisions: objects deform, stick together, and/or bounce imperfectly
Momentum is conserved: the total momentum of all objects before a collision is the
same as after the collision.
1) A hydro-electric dam has water fall through a turbine
to generate electricity. Find the force of gravity on 1 kg
of water. How many joules would this produce if the
turbine is pulled 10 meters at a time?
1.
2.
3.
4.
5.
6.
100 W
1000 W
10 W
100 J
1000 J
10 J
55%
27%
9%
9%
0%
1
2
0%
3
4
5
6
2) A person on a bicycle has a downward force
of 1000 N. They coast 2500 m along a flat road.
How much work is done?
1. 2500000 J
50%
2. 2.5 J
3. 1500 N
30%
4. 3500 J
5. None of the above
10%
10%
0%
1
2
3
4
5
3) A lightbulb uses 60W. A battery stores 6000 J. For
how many seconds can the battery power the
lightbulb?
1.
2.
3.
4.
360000 s
100 s
1000 s
Cannot be
determined
5. None of the above
0%
1
0%
0%
2
3
0%
0%
4
5
4) A motor boat’s engine uses 5,000 J of energy
in only 4 seconds. How powerful is it?
1.
2.
3.
4.
5.
20,000 W
1250 W
5004 W
4996 W
None of the above
0%
1
0%
0%
2
3
0%
0%
4
5
8) Wiley Coyote accidentally steps off of a 2000 m tall
cliff. He has a mass of 10 kg. How fast will he be going
when he hits the ground?
1.
2.
3.
4.
5.
200,000J
20J
200 m/s
40,000 m/s
None of the above
0%
1
0%
0%
2
3
0%
4
0%
5
9) A shopping cart starts at rest and rolls down a hill,
picking up speed. At the bottom, it is going 4 m/s.
How tall was the hill?
(You do not need to know the mass of the shopping
cart to solve this. Set it up and see why.)
1.
2.
3.
4.
5.
0.4 m
0.8 m
40 m
80 m
None of the above
0%
1
0%
2
0%
3
0%
4
0%
5