A person exerts a power of 175W in lifting a 102.0 kg object vertically at a distance of 2.5 m in a time of 2.3 s.?
What is the percent efficiency of the lift?
- oldschoolLv 76 months ago
Work done = mgh = 102kg * 9.8m/s² *2.5m = 2499J
2499J/2.3s = 1087J/s = 1087W
Check your numbers. Is that 102N?
102N*2.5m/2.3s = 111W
111/175 = 63.4%
Maybe that is 10.2kg
mgh = 10.2*9.8*2.5 = 249.9J
108.7/175 = 62.0%
- Anonymous6 months ago
power = mass * g * height / time
efficiency = power from above / 175 W * 100