Question
A body of mass m is taken up with constant velocity through height h. What is the work done by external force in taking the body up?
Solution
Work done by force is given by,
To move the body up with constant velocity, the external force equal to mg must be applied in upward direction.
Here both the external force and displacement are in same direction.
Therefore angle between force and displacement is zero.
Now work done by external force is,
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To move the body up with constant velocity, the external force equal to mg must be applied in upward direction.
Here both the external force and displacement are in same direction.
Therefore angle between force and displacement is zero.
Now work done by external force is,
