From where does earth get energy for rotation?

AI Thread Summary
Earth's rotation is sustained by the principles of Newton's first law and the conservation of energy, meaning no additional energy input is required to maintain its motion. Once the Earth begins to rotate, it continues to do so without needing energy, as it is not working against the sun's gravity. The discussion emphasizes that energy is only needed to stop the rotation, not to maintain it. The initial energy for Earth's rotation comes from the conditions of its formation. Understanding these principles clarifies the mechanics behind planetary rotation.
joyever
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from where does Earth get energy for rotation?as its rotating means its doing some motion to work again sun's gravity soo from where does Earth gets this energy?
 
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No, the Earth is not doing work against the sun, so no input is required.
 
but anyhow how Earth gets energy for rotation?
 
Like I said, no energy input is required. That is due to Newton's first law and conservation of energy.
 
google... "why do planets rotate"

And once they "start" they don't need energy, as Russ explained.
 
Once something is rotating, it doesn't need energy to keep on rotating. In fact, it needs energy to STOP it from rotating.
 

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