Why Does a Ball Thrown Upwards Return at the Same Speed?

AI Thread Summary
A ball thrown upwards returns at the same speed due to the conservation of energy principles. As the ball ascends, its kinetic energy decreases while potential energy increases, and vice versa during its descent. The time taken for the upward and downward movements is equal, resulting in the same speed upon return. This phenomenon illustrates the balance between kinetic and potential energy throughout the ball's trajectory. Understanding this concept is fundamental in physics.
quark001
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My high school physics textbook says that the speed at which a ball leaves your hand (when thrown upwards) is the same as the speed at which you catch it (if you don't move your hand). That means that the time for the ball's upwards movement is the same as for its downwards movement. Why is this?
 
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Moving up: The potential energy increases while the kinetic decreases(smaller velocity)
Down: The kinetic energy increases while the potential decreases.

So it is a matter of conservation of energy.
 
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