Download Energy Skate Park Lab SECTION 1 – Energy Transformation Go to

Energy Skate Park Lab
SECTION 1 – Energy Transformation
Go to http://phet.colorado.edu/ and type in the search bar: skate. Select Energy Skate Park: Basics and then Run in
HTML5.
Click on the Intro tab/screen. Use the “U” shaped track and select the speed box so the speedometer shows up.
1. When does the skater have the most kinetic energy?
2. When does the skater have the most potential energy?
Now select the bar graph.
3. Explain how the bar graphs visually keep track of energy. Snip a picture of the bar graph at the top, at a point
exactly half of the maximum height, and at the bottom of the track. Describe how the three types of energy,
total, kinetic and potential change as the skater moves down the track.
Point
Top –
Mid point. Bottom Description of Energy Changes
max
– h = ½ of – min.
height
max.
height,
height.
h=0
Snip of Bar Graph
4. Once the skater is placed on the track (and when it moves up and down) does the total energy bar change
heights? Explain why that is.
Now select the pie chart.
5. Explain how the pie chart visually keep track of energy. Snip a picture of the pie chart at the top, at a point
exactly half of the maximum height, and at the bottom of the track. Describe how the three types of energy,
total, kinetic and potential change as the skater moves down the track.
Point
Top –
Mid point. Bottom Description of Energy Changes
max
– h = ½ of – min.
height
max.
height,
height.
h=0
Snip of Pie Chart
6. How do pie charts represent the total amount of energy available? Does this representation follow the law of
conservation of energy?
7. What are some advantages to representing the energy with bar graphs?
8. What are some advantages to representing the energy with bar graphs?
9. Which do you prefer and why?
10. What can you do that will change the total energy in the skater/track system?
There are TWO – 2 – correct answers. Use the equation for Potential Energy to help you answer this question.
Continued on the next page
Section 2 – Assessing Energy Transformation
Continued…
Section 2 – Assessing Energy Transformation
Click on the “Playground table and Create the Track
Shown. Be sure to match the track usin the grid. The
highest points (A & H) are at 8.0 meters. Point D is at
4.0 meters. Points C & E are at 0.0 meters. On this
image you see 8 pink points labeled A – H.
On a scale of 0-8 (0 being the least, 8 being
the most), predict the amount of kinetic
and potential energy when the skater is on
different parts of the track.
Point
Prediction
A
PE
B
KE
PE
C
KE
PE
D
KE
PE
E
KE
PE
F
KE
PE
KE
G
H
PE KE PE KE
Then place the skater at point A and see if your predictions were correct
Section 3 - Friction
READ: Energy is not created or destroyed; it is simply transferred from one storage place to another. This is the law of
conservation of energy. It is not the same thing as “conserving energy”, which implies that we need to limit our
energy usage and use our resources wisely. The conservation of energy is one of the most important ideas in
science.
Now click on the friction tab/screen.
Investigate how friction affects the energy of the skater/ramp system. Experiment with all three track shapes.
1. How does increasing the friction affect the charts/graphs?
2. Why, when friction is present, does the skater eventually stop?
Use the conservation of energy in your answer
Section 4 - Effect of Starting Height and track length on PE and KE
1. Start your skater at the top of the track. Predict what height you think the skater will reach on the other
side. Snip and Paste or write what happened to the skater. Write a possible reason why.
Position of Skater
Prediction
Result
Possible reasons why it
happened.
2. Drag and drop your skater half way up the track. Predict what height you think the skater will reach on the
other side. Snip and Paste or write what happened to the skater. Write a possible reason why.
Position of Skater
Prediction.
Result
Possible reasons why it
happened.
3. Make the right side of the track longer. Start your skater on the right side. Predict what you think will happen
on the other side. Snip and Paste or write what happened to the skater. Write a possible reason why.
Right side longer
Prediction
Result
Possible reasons why it
happened
4. Make the left side of the track longer with a short right side. Start your skater on the right side. Predict
what you think will happen on the other side. Snip and Paste or write what happened to the skater. Write a
possible reason why.
Left side longer
Prediction
Result
Possible reasons why it
happened
5. Using the conservation of energy, write an explanation of how starting height affects the maximum height a skater
will reach.
6. How will turning friction on affect the maximum height a skater will reach? Will the maximum height a skater can
reach stay the same, increase, or decrease. Use the conservation of energy in your answer. Use the simulation to test
and verify your answer.
Continue to Section 5
Experiments!
Continue to Section 4
Section 5 – Designing Experiments
#1 – Does Mass Affect Speed?
Go to http://phet.colorado.edu/ and type in the search bar: skate. Select Energy Skate Park: Basics and then Run in HTML5.
Friction Tab – Friction OFF
…Then Turned ON
U-Pipe track
Observe the skater moving from one side to the other, specifically, the speed of the skater at the lowest point. Change
the mass of the skater and observe how the size of the skater changes. Compare changes of mass to any possible
changes in speed.
Repeat your experiment with the friction turned on to a constant amount for both masses. Describe any changes to the
results.
Use visual evidence to support your answer and explain and how your evidence proves you are correct.
# 2 – Does Direction Affect Speed?
Friction Tab - Friction is OFF…
Go to http://phet.colorado.edu/ and type in the search bar: skate. Select Energy Skate Park: Basics and then Run in HTML5.
…Then Turned On.
U-Pipe track
Observe the skater moving from one side to the other, specifically, the speed of the skater at any specific height. Is the
skater moving faster as they are traveling up the ramp, or down the ramp, when they reach that specific height?
Repeat your experiment with the friction turned on to a constant amount. Describe any changes to the results.
Use visual evidence to support your answer. Describe your thought process or procedure and how your evidence proves
you are correct.
#3 – Does the shape of the track affect final height reached?
Go to http://phet.colorado.edu/ and type in the search bar: skate. Select Energy Skate Park: Basics and then Run in HTML5.
Track Playground Tab - Friction is OFF
…Then Turned On
You will build three – 3- different tracks. All tracks will begin and end at the same height.
The shape of the tracks will differ. One track will be a traditionally shaped U-pipe with its
lowest point in the center, an equal distance from the ends. The other two tracks should
be lopsided, with their lowest point closer to either the left or right side. An example of a
track with its lowest end closer to the left is shown.
Repeat your experiment with the friction turned on to a constant amount. Describe any changes to the results.
Using visual evidence to support your answer. Using the conservation of energy, explain why these results occur.
Last Section – Section 6 – Continued
USING NON-BASIC SKATE PARK
Section 6 – Predict & Calculate Values for Kinetic and Potential Energy
Energy Skate Park
(Non-Basic)
http://phet.colorado.edu/en/simulation/energy-skate-park
U-Pipe track
Friction is OFF
Track Extended to the Ground. Potential Energy Reference line On the Ground
Choose a skater and record a value of mass
m = _____ kg
Place the skater at a height of your choosing on the U-Pipe and record the value of a maximum height of your choosing
h = _____m
Calculate and record the potential energy of your skater at the maximum height of your choosing
PE = ________ J
Using your knowledge of the conservation of energy, predict the value of kinetic energy at the lowest point.
KE = ______ J
Using Algebra, and the value of mass, calculate the velocity of the skater.
V = ____ m/s
Repeat this process for a point on the track exactly half of your chosen maximum height.
Choose a skater and record a value of mass
m = _____ kg
Place the skater at a height of your choosing on the U-Pipe and record the value of a maximum height of your choosing
h = _____m
Calculate and record the potential energy of your skater at the half of maximum height of your choosing
PE = ________ J
Using your knowledge of the conservation of energy, predict the value of kinetic energy at that point.
KE = ______ J
Using Algebra, and the value of mass, calculate the velocity of the skater.
V = ____ m/s
Carefully follow the direction to see if your calculated values were correct.
Click on “Show Path” on the Control Panel.
Allow the skater to repeat the process. You should see dots created along the skater’s path.
Right click on the dot at the maximum height, the lowest point, and at a point exactly half of the maximum height.
Compare your predicted and calculated values to the values shown.
Calculate your percent error for your grade!
Percent Error for Predicted / Calculate Value for Velocity @ point exactly half of maximum height __________