6) 500J of work is required by a machine to raise a load of 250N through a vertical distance of 1.6m. the efficiency of the machine is (a) 80% (b) 75% (c) 67% (d) 50%
To find the efficiency of the machine, we can use the formula:
Efficiency = (useful output energy / input energy) * 100%
Given that the input energy is 500J and the machine is raising a load of 250N through a vertical distance of 1.6m, we can calculate the useful output energy:
Useful output energy = force * distance
= 250N * 1.6m
= 400J
Now we can calculate the efficiency:
Efficiency = (400J / 500J) * 100%
≈ 80%
Therefore, the efficiency of the machine is approximately 80%.
(a) 80%