1. Why does the total energy stay constant while the amount of PE and KE changes as the skater moves back and forth on the ramp ?

2. How does the friction affect the skateboarder’s movement?

3. As the skateboard goes back and forth on the ramp, how does thermal energy change ?

Answer:

Step-by-step explanation:

1. Why does the total energy stay constant while the amount of PE and KE changes as the skater moves back and forth on the ramp ?

The law of conservation of energy states that energy can neither be created nor destroyed - only converted from one form of energy to another. This means that a system always has the same amount of energy, unless it's added from the outside. In case of skater moves back and forth on the ramp, the total energy stays the same as he moves down the ramp, since energy is converting and not going anywhere. 

2. How does the friction affect the skateboarder’s movement?

The greater the gravity, the faster the skateboarder goes and the lesser the gravity, the slower the skateboarder goes. The greater the friction, the slower the skateboarder goes and the lesser the friction, the faster the skateboarder goes.

3. As the skateboard goes back and forth on the ramp, how does thermal energy change ?

As the skateboarder goes down the ramp, potential energy is converted to kinetic energy. Because of friction, some of the energy in the system is converted to heat energy. Once the kinetic energy is converted to heat, the energy cannot be converted back to the potential or kinetic energy in the system.