Newton's Laws - Pushing on a heavy object

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SUMMARY

This discussion centers on the application of Newton's Laws of Motion, specifically regarding the interaction between a person and a massive object, such as a mountain or the Earth. When a person pushes against a heavy object, the object exerts an equal and opposite force, resulting in an infinitesimal displacement of the object due to the vast difference in mass. The discussion concludes that while the force exerted by a person does not result in noticeable movement of the mountain, it does create a minuscule displacement, estimated at around 10-21 centimeters when considering the Earth itself.

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I'm trying to understand if a really heavy object on earth, say a mountain, would move if I push it with my bare hands. This sounds absurd but according to Newton's Laws, if I push against the mountain it will exert an equal and opposite force. I understand there are other forces like gravity and friction involved but does it mean that me pushing on it will effectively move the mountain and because of the astronomical difference in the mass between me and the mountain, the effect will be infinitesimally small? or is it that there will be absolutely zero displacement?
 
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You will be pushing on the mountain, which will exert a force back on you, and all you will end up doing is moving a little bit of dirt around as you hands and feet slide around. Other than the dirt there will be no displacement because the mountain is part of the ground and is held there through atomic/molecular forces. If you were both floating in space and you pushed off the mountain then both you and the mountain would begin to move apart.
 
Einstein said:
I'm trying to understand if a really heavy object on earth, say a mountain, would move if I push it with my bare hands. This sounds absurd but according to Newton's Laws, if I push against the mountain it will exert an equal and opposite force. I understand there are other forces like gravity and friction involved but does it mean that me pushing on it will effectively move the mountain and because of the astronomical difference in the mass between me and the mountain, the effect will be infinitesimally small? or is it that there will be absolutely zero displacement?

How about running this experiment on a really heavy object, in fact the most massive object on earth? That most massive object is... The Earth itself!

All you need to to do is to jump. Your feet are pushing on the earth, and the Earth is pushing back with an equal and opposite force. The force of the Earth pushing against your feet will throw you into the air (how high can you jump?). Meanwhile your feet pushing on the Earth will move it ever so slightly in the opposite direction. How slightly? Well for reasonable assumptions about your weight and strength, maybe 10-21 centimeters, which is well and thoroughly undetectable.

So to answer your question: not truly zero, but infinitesimally small.
 

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