Pls show me the steps how to work this physics question:A pulley system of 4 pulleys is used to raise a loan of mass 50kg vertically,if its effeciency is 80%,determine the minimum effort required to raise the load(g=10ms-2)?

1 answer

the weight is 500N

80% efficiency means that 1/.8 = 1.25 the weight is needed.