SOLUTION: A solid object with mass (m) is initially at rest. An applied constant vertical force (F) causes the object to reach an upward speed (V), and the total displacement (h). Use Newton

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Question 436334: A solid object with mass (m) is initially at rest. An applied constant vertical force (F) causes the object to reach an upward speed (V), and the total displacement (h). Use Newton's second law to derive an expression (in terms of m,g,h, & V) for the work.
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
Since Work = Force*distance, we can use F%5Bnet%5D+=+ma where F%5Bnet%5D+=+F+-+mg, because the object is subjected to both F and its own weight. However there is a much faster way:

Note that the work done is equal to the total change in energy of the object. This is equal to the sum of the potential and kinetic energies gained, which is equal to mgh+%2B+%281%2F2%29mV%5E2 (mgh represents the potential energy and %281%2F2%29mV%5E2 is the kinetic energy of the object). Hence, this is the amount of work done.