|MadSci Network: Physics|
The impulse that you feel as the falling object hits your hand comes from the momentum of that object relative to your hand. You have the correct idea about why this impulse seems to be less because your hand is moving in the same direction as the falling object. The momentum (calculated as mass times velocity) comes from the relative velocity of the objects. Because your hand and the falling object are moving in the same direction, the relative velocity is reduced. If you were moving your hand toward the falling object the relative velocity is increased. This type of problem is often assigned to students in physics classes. John Haberman
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