A boy thrown a rubber ball vertically upwards. What type of work positive or negative, is done :

(a) By the force applied by the boy?


(b) By the gravitational force of earth?

Work done by the two forces in the given condition is :

a) Work done by the force applied by the boy is positive due to reason that the displacement of the ball is in the direction of the force applied.


b) Work done by the gravitational force of earth is negative. This is because the displacement of the ball is opposite to the direction of the gravitational force.


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