A ball is thrown straight upward with an initial speed v0. When it reaches the top of its flight at height h, a second ball is thrown straight upward with the same initial speed. Do the balls cross paths at height 1/2h, above 1/2h, or below 1/2h

The balls cross paths above 1/2h

Explanation:

Let's analyze the picture when the first ball is at the top of its flight and the second ball starts to flight.

When the second ball is thrown it has the maximum speed and the first ball starts with an initial velocity equal to zero. We know that they will cross at the same time, hence the second ball will travel a longer distance, due to its velocity, than the first ball.

Therefore, the correct answer is above the midpoint of h (1/2h).

I hope it helps you!  

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