Couple of Physics Question dealing with momentum, force, etc

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When pulling a cart at a constant velocity, the net force is zero, as the forces acting on the cart are balanced. When a baseball is thrown into the air, it experiences its weight acting downward and an upward force during its initial ascent, but the net force becomes zero at the peak of its trajectory. As the ball falls, it only experiences the force of gravity, leading to a downward acceleration. The discussion emphasizes the importance of understanding net forces in relation to motion and gravity. Overall, the concepts of force and momentum are crucial to analyzing these physics scenarios.
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Suppose I am pulling on a cart at a constant velocity, what is my net force. Is it zero?

If I throw a baseball in the air, neglecting air resistance, what does the ball experience when it comes out your hand and before it hits the ground? does it experience it's weight and also a decreasing upward force.
 
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Net force is zero if there is no friction.
Well, ball feels the same force (assuming both events are on equal height, like I think it was meant)
 

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