Lesson 18, Physical Science
Please help!! I'll mark you as Brainlest

Q1. Describe how the skater's kinetic and potential energy change as the skater descends. Explain what happens to the total energy (potential energy + kinetic energy) in terms of the Law of Conservation of Energy.
Change the skater with the "Choose Skater" button.






Q2. Describe any changes to the bar graphs you see when you change skaters. Is the Law of Conservation of Energy still obeyed?

Reset the half-pipe and click on the "Show Grid" check box. Grab the track (drag the track with a right-click) and set the bottom of the track at "zero" height.
Select the default, 75 kg, PhET skater and set him at 5.0 meters above the zero and allow him to skate.
Q3. How much potential energy does the skater have at 5.0 meters? How much kinetic energy does the skater have at 0.0 meters?

Q4. If a 20.0 kg skater started his skate at 10 meters height (on Earth):
How much potential energy would the skater have at the start of skating?
How much kinetic energy would the skater have at the start of skating?
How much potential energy would the skater have at zero height?
How much kinetic energy would the skater have at zero height?


Create this skate path:


Start the skater on the left side and observe. Then answer the following question:
Q5. Does the skater have enough energy to make it all the way to the right side? Explain why or why not.

If the skater starts on the left on the following path:


Q6. Answer the parts of this question based upon the above skater path. If the skater starts at point "A":

Where does the skater have the maximum potential energy?
Where does the skater have the minimum potential energy?
Where does the skater have the minimum kinetic energy?
Where does the skater have the maximum kinetic energy?
At which two points would the skater have about the same kinetic energy?

Q7. Based upon the equation for potential energy, how do you expect the potential energy to change when the gravity is lower than it is on Earth (for example, gravity on the moon is 1.6 m/s2 )?

Use the option boxes to move the skater to Jupiter, where acceleration due to gravity is 26 m/s2.

Q8. Describe any differences you see in potential and kinetic energy between the Earth and Jupiter.
Use the option boxes to move the skater to the moon where the acceleration from gravity is 1.6 m/s2.

Q9. Describe any differences you see in potential and kinetic energy between the Earth and the moon.

Q10. Does this agree with the prediction you made in Q7?

Q11. How high must a 20 kg skater start at to have a kinetic energy of 360 joules at a height of 0 meters?

Q12. What is the total energy of the 60.0 kg skater before she starts her ride, 12 meters above the ground?

Q13. If you throw a 2.0 kg basketball straight up in the air, at what height will the basketball have 160 J of potential energy?

Q14. Describe what happens to the bar graphs when you change the amount of friction. Is the Law of Conservation of Energy still obeyed?