Gravitational potential energy negative?

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Kinetic energy is always positive, while gravitational potential energy (PE) can be negative depending on the chosen reference point. The value of gravitational PE is relative and is defined based on where PE equals zero. Only changes in gravitational PE are significant in physical calculations. Understanding these concepts is crucial for grasping the principles of energy in physics. The discussion highlights the importance of reference points in determining gravitational potential energy.
mrserv0n
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Can kinetic energy of a system or gravitational potential energy be negative?

I am reading about the two but its very complex and can't seem to describe why.
 
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Kinetic energy must be positive, but gravitational PE can certainly be negative. Gravitational PE depends on what you choose as your (arbitrary) reference point, where you define PE = 0. (Only changes in PE are physically significant.)
 

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