Does Potential Energy Equal Kinetic Energy at the Bottom of a Hill?

AI Thread Summary
When an object descends a hill, its potential energy converts to kinetic energy, assuming only conservative forces like gravity are at play. In this scenario, if the potential energy at the top is 7,350 J, then at the bottom, the kinetic energy would also be 7,350 J, reflecting the conservation of mechanical energy. If non-conservative forces, such as friction, are present, some potential energy would be lost, resulting in less kinetic energy. However, the discussion clarifies that friction is ignored in this case. Thus, the potential energy equals kinetic energy at the bottom of the hill under the given conditions.
Chuck Norris
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Homework Statement


Say your potential energy at the top of a hill is 7,350 J. At the bottom of the hill wouldn't the kinetic energy then be 7,350 J?


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Hi Chuck Norris,

Assuming only conservative forces (like gravity) act on the object, then yes, mechanical energy will be conserved, and all of the potential energy at the top of the hill will have been converted into kinetic energy at the bottom of the hill. However, if there are non-conservative forces, such as friction, then some of the potential energy will be wasted and not all of it will be converted into energy of motion.
 
Ok thanks that is what I thought. In the original question is says if friction can be ignored. So I believe that we are acting as if there is no friction involved. Thanks for your help.
 
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