Post on 22-Feb-2016
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SKATE PARK PHYSICSPhysics is PhunSkate Park Physics
Before we get started lets go to the link below and open the skate park sim
http://phet.colorado.edu/en/simulation/energy-skate-park-basics
FrictionSet the grid in the background.1. Explore what would happen with no
frictiona. How does the skaters starting point
compare with the ending point?b. What happens when you increase
the friction?c. Find the friction for the skater.
EnergyCheck the square for the pie chart. Notice the colors-thermal, kinetic, potential.
1. How does the kinetic energy relate to potential energy?
2. Why is thermal energy absent?3. What happens when we increase friction?4. How does the pi chart effectively communicate
the law of conservation of energy.
Energy Cont.Check the bar graph. Run the program noticing how the energy
is shown on the bar graph.
SpeedCheck the box for the speedometer.1. How would you describe the speed at
various points on the track?2. Where is the speed the greatest?
Describe the types of energy at this point.
3. Where is the speed the least? Describe the types of energy at this point.
Further ObservationsTake a few minutes and try the other track options. Observe the speed, energy. Vary the friction of the skateboarder.
How are speed and energy related?
Kinetic and Potential Energy
The formula for kinetic energy is mv2.
The formula for potential energy is mgh.
Because of conservation of energy mv2 + mgh on a frictionless track is equal throughout the track. The mass, the acceleration of gravity are constant and the velocity and the height of the skater are variables.
If a 40 kg skater is 3 meters off the ground at the beginning of his skate what is his velocity at the bottom of
the hill?
The equation would look like this
mv2 TOP+ mghTOP = mv2
TOP + mghTOP
(40kg)(0 )2 +(40kg)(9.8 )(3m)= (40kg)v 2+(40kg)(9.8)(0m)
Solve for the velocity
Do you where do you think the skater is located for each of the
following graphs? Is friction turned off or on?
Draw a bar chart for each position.Assume the friction is turned off.Assume A is the starting point.
A
B
C
D
Draw a bar chart for each position.Assume the friction is turned on.Assume A is the starting point.
A
B
C
D
Make your own skate park.
Now create your own skate park. How does the law of conservation of energy influence your considerations.
Physics is Phun
Tennessee Standards Check 3231.1.17 Investigate the definitions of
force, …, kinetic energy, and potential energy.Kinetic Energy: EK = 0.5mvPotential Energy: EP = mg∆h.
SPI.3231.1.6 Given the static and kinetic friction coefficients (μs and μk);
select the appropriate coefficient of friction and calculate
the force necessary to move the object.