What Type of Energy Conversion Occurs When a Cable Car Runs Downhill?

AI Thread Summary
When a San Francisco cable car runs downhill from a height of 30 meters without friction, it converts potential energy into kinetic energy. At the top of the hill, the cable car possesses potential energy, which transforms into kinetic energy as it descends. The absence of friction means no heat energy is generated during this process. Therefore, the correct answer to the energy conversion is option a: potential energy to kinetic energy. This illustrates the fundamental principles of energy transformation in a frictionless environment.
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Homework Statement


A San Francisco cable car loses its brakes and runs down a hill 30 m high. Assuming there is no friction, which of the following represents the energy changes that occurred?

a. potential energy to kinetic energy
b. kinetic energy to potential energy
c. potential energy to heat energy to kinetic energy


Homework Equations


Potential Energy - The energy possessed by a body by virtue of its position relative to others, stresses within itself, electric charge, and other factors.
Kinetic Energy - Energy that a body possesses by virtue of being in motion.


The Attempt at a Solution


a. potential energy to kinetic energy


Is the correct answer a.?
 
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Given the choices, why do you say 'a' is correct? Please explain.
 
PhanthomJay said:
Given the choices, why do you say 'a' is correct? Please explain.

At the top of the hill, while the car is parked, it has potential energy. While the car is going down the hill it has kinetic energy because it is in motion. I don't think heat energy was produced because there was no friction. So that's why I picked a. :smile:
 
That is right ! :)
 
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