Answer: 0.51 J
Explanation:
The work done on the ball is equal to the sum of two terms:
- the work done in lifting the ball by 1.32 m
- the work done by the frictional force of 0.350 N that acts opposite to the motion; this work is negative, since the force acts in the opposite direction to the motion of the ball.
In formulas, the net work done is:
[tex]W=mgh - F_f h[/tex]
where
m = 0.075 kg is the ball's mass
g = 9.8 m/s^2 is the gravitational acceleration
h = 1.32 m is the height throug which the ball has been moved
Ff = 0.350 N is the frictional force
Substituting, we find
[tex]W=(0.075 kg)(9.8 m/s^2)(1.32 m)-(0.350 N)(1.32 m)=0.51 J[/tex]
