Answer:
work done on desk = m g h = 105 * 9.81 * 2.46 = 2534 Joules
Explanation:
so work in = 2534 / 0.875 = 2896 Joules
that is your 648 times distance your hand moved holding the rope
2896 = 648 * x
4.47 meters
I think maybe a typo, 648 N is too big, maybe 64.8 ? Any block and tackle system does better than that.
C) explore alternative sources of energy, such as solar energy
The time spent in the air by the ball at the given momentum is 6.43 s.
The given parameters;
- <em>momentum of the ball, P = 0.9 kgm/s</em>
- <em>weight of the ball, W = 0.14 N</em>
The impulse experienced by the ball is calculated as follows;

where;
is impulse
is change in momentum
The time of motion of the ball is calculated as follows;

Thus, the time spent in the air by the ball at the given momentum is 6.43 s.
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