Why does a ball move in your hand when net forces are 0?

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SUMMARY

The discussion centers on the concept of net force and motion, specifically addressing why a ball continues to move in hand when net forces are zero. When a ball is pushed upwards, it experiences positive acceleration until it reaches a constant velocity, at which point the net force is zero. This occurs because the upward force exerted by the hand and the downward forces of gravity and air friction balance each other out, resulting in no net force acting on the ball.

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Matt Poirier
This is a more general and probably silly question, but if you have a ball in your hand and you move it upwards, the acceleration will be positive then after you move it at constant velocity, acceleration will be 0. However, how is net force is 0 when the ball is still moving? You are clearly still pushing on the ball, so does your hand's push and air friction cancel so net force is 0?

<Moderator's note: Moved from a homework forum (general concept) and template removed.>
 
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Matt Poirier said:
You are clearly still pushing on the ball, so does your hand's push and air friction cancel so net force is 0?
You forgot gravity, but yes, the net force being zero is not the same as all individual forces being zero, just the sum of them.
 

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