Question

The efficiency of a machine is 80% calculate the work done by a person using the machine to raise a load of 300kg through a height of 4m (take g=10/s2)

Answer 1

work = force * distance
But you only get to use 80% of the work input. That means that
0.8W = 300*10*4

Answer 2

I need the answer

Answer 3

62500 i think

Answer 4

Efficiency=work out put/work input x 100
80/100=200 x 3 x 10/x
80x=600000
x=7500j

Answer 5

7500j

Answer 6

1500j

Answer 7

300×10×4×100/80