Work done by a person lifting and then throwing a ball

AI Thread Summary
To calculate the total work done when lifting and throwing a ball, one must consider both the lifting and throwing phases. The initial work done in lifting the 5 kg ball to 1.5 meters is calculated using W = mgh, resulting in 73.5 joules. However, this only accounts for the lifting; additional work is required to throw the ball to a height of 10 meters. The throwing phase involves applying a significant force over a short distance to impart the necessary velocity. Therefore, the total work includes both the lifting and the work done during the throw.
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If I lift a ball of mass 5 kg from ground level to 1.5 meters above ground level and then throw it from this point up to a height of 10 meters, what is the work done by me on the ball?

Is the following the correct way to solve this problem?

Person only applies force to the ball for 1.5 meters so the work he does is simply W = mgh = (5)(9.8)(1.5)

thanks in advance.
 
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That calculation only covers the lifting work, not the throwing work. In throwing, you will have to apply a very large force over a short time and distance, in order to give it the velocity that will take it to a height of 10m. The distance is limited by how high the ball is when your hands lose contact with it - and hence cease applying force to it.
 
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