How efficient is a pulley system if an operator has to pull 2.5m of rope to lift a 250 N pail of water a distance of 4.5 m?

the pulley system is very efficient

Explanation:

Given;

load, L  = 250 N

distance moved by the load, a = 4.5 m

distance moved by the effort, e = 2.5 m

let the force or effort applied = F

Apply the principle of conservation of energy;

F x e = L x a

F = (L x a) / e

F = (250 x 4.5) / 2.5

F = 450 N

The efficient of the pulley system;

E = Output force / Input force

E = (450 x 2.5) / (250 x 4.5)

E = 1 = 100%

Therefore, the pulley system is very efficient

i think it’s a. this is because if they measured the mass of something with a mass of 150g, then their final answer would have to be approximately 150g. though all of their answers are almost 150, rosa and tran have the closest answers (or the exact answer) to the accurate one.