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Confused about the role of mass

why is it that two object of varying mass will fall at the same speed in a frictionless enviorment like the moon? Is it because the object needs to overcome more momentum or what?

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marked as duplicate by Qmechanic, David Z Nov 15 '11 at 23:10

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

up vote 1 down vote accepted

This happens because the gravitational mass of an object is equal to the inertial mass of an object. Because of this, the acceleration of an object in a gravitational field does not depend on the mass of the object.

For example, if you double an object's mass, the force required to accelerate it by the same amount as before doubles, but the gravitational force pulling it down also doubles. The effect of any mass changes cancel out.

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