The first item is a 100 kg piano which hauled upward by a rope and pulley system

Question

The first item is a 100 kg piano which hauled upward by a rope and pulley system to the second floor foyer.

1.1. If the piano does not accelerate, what is the tension force, T, applied to the piano?

1.2 How much work is required to pull the piano a distance 5.0m up to the second floor?

A second, very pumped up, friend decides to help pull an additional 5.0 m. The piano accelerates at a rate of 0.2 g.

1.3 What is the net work done on the piano?

1.4 What is the speed of the piano after it travels 5m?

Explanation / Answer

1.1
Tension must balance the weight
T = m*g
   =100*9.8
   = 980 N

1.2
work done = T* distance
                     = 980*5
                     =4900 J

1.3
Force applied, F = m*(g+a)
                               = 100*(g+ 0.2*g)
                               = 100*(1.2 g)
                               = 100*1.2*9.8
                               = 1176 N

1.4
Work done = F*d
                      = 1176*5
                      =5880 J

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