Different types of energy: kinetic vs potential vs

AI Thread Summary
A blackboard eraser held steady three feet above the ground possesses potential energy due to its height, while its kinetic energy is zero since it is not moving. The discussion clarifies that kinetic energy is associated with motion, and potential energy is related to an object's position and its ability to convert to kinetic energy. If the eraser were released, it would then convert its potential energy into kinetic energy as it falls. The distinction between these energy types is emphasized, noting that being still does not inherently confer potential energy without a height reference. Understanding these concepts is crucial for grasping the principles of energy transformation.
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1. Homework Statement

What type of energy does a blackboard eraser have when I hold it steady three feet about the ground?

a. potential energy
b. kinetic energy
c. electrical energy
d. spring elastic energy


I think it is kinetic energy. But I am confused on the differences of types of energies.
 
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Kinetic energy is what an object has when it is moving, so if you hold the eraser steady, it's kinetic energy will be equal to zero.

Think about what would happen if you let go of the eraser.
 
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Tell us what do you know about the 4 types of energies.
 
It's potential energy while it is still. and then kinetic if you start moving the eraser.
 
It's potential only if it has a relative height associated with it. For example, if the reference point is the floor and the eraser is held still on the floor then the kinetic energy is zero but the potential energy is also zero.

So being still is not itself the reason for something having potential energy. Think of potential energy as having the potential to transform into kinetic energy.
 
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