Another conservation of energy problem

AI Thread Summary
The discussion centers on the relationship between gravitational potential energy (PE) and kinetic energy (KE) in the context of energy conservation. When a ball is dropped, its potential energy converts to kinetic energy, illustrating that energy is conserved in a closed system. The key point is that the change in potential energy as the ball falls results in an equal change in kinetic energy. This principle highlights that gravity is the sole force acting on the ball during its descent. Understanding this relationship clarifies why gravitational potential energy is not inherently equal to kinetic energy, but rather transforms between the two forms as energy is conserved.
physicsman2
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Homework Statement


why is the gravitational potential energy of a ball equal to its kinetic energy


Homework Equations


KE=PE


The Attempt at a Solution


im really not sure, i think its because energy is conserved but i don't know why that is either
 
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Yes, it has to do with the conservation of energy. Think of it this way - If you hold a ball in your hand and drop it, the kinetic energy will equal the gravitational potential energy, because the ball cannot acquire energy from any other source. Gravity is the only thing pulling the ball down - no other force is going to help the ball fall.
 
oh i understand now thanks
 
physicsman2 said:
why is the gravitational potential energy of a ball equal to its kinetic energy

As stated it is not.

The conservation of energy tells you however that the Δ in potential energy will manifest as a Δ in kinetic energy when a ball is released in a gravitational field.
 

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