Download Energy Skate Park Lab Go to http://phet.colorado.edu/ and type in

Energy Skate Park Lab
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. Draw an example.
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 pie charts track the energy. Draw an example.
6. How do pie charts represent the idea of question #4?
7. What can you do that will change the total energy in the skater/track system?
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.
8. Investigate how friction affects the energy of the skater/ramp system. Experiment with all three track shapes.
How does increasing the friction affect the charts/graphs?
9. What are some advantages to representing the energy with bar graphs?
10. What are some advantages to representing the energy with pie charts?
11. Predict (draw) what the energy pie charts will look like at A, B, C and D. Assume no friction.
A
C
D
Position
Prediction
B
A
B
C
Now click on the playground tab/screen.
12. Move the friction slider to “none”. Did you predict correctly? Explain.
D
Effect of Starting Height on PE and KE
Drag and drop your skater half way up the track. Draw or write what happened to the skater.
Position of Skater
Result
What do you notice about the bar graph, now, compared to when the skater started higher up on the track?
Effect of Length of the Track
Make the right side of the track longer. Start your skater on the right side and draw or write what happens to the
skater.
Right side longer
Result
Possible reasons why it
happened
Make the left side of the track longer with a short right side. Start the skater on the right side again, and draw
or write what happens to the skater.
Left side longer
Result
Possible reasons why it
happened
Pendulum PE and KE
the Pendulum link. Or type in http://phet.colorado.edu/en/simulation/pendulum-lab
Click Show energy of 1 ….
and 1/16 time
Drag and release the pendulum to set it in motion. Watch the graph of PE and KE.
Label the points on the pendulum’s path where PE and KE are at their maximum.
CONTINUE
How does the PE and KE of the Pendulum compare to the Skate Park?
#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.
TWO MORE PROBLEMS ON THE BACK USING NON-BASIC SKATE PARK
#4 – 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 __________