Answer:
Explanation:
efficiency = (energy output / energy input)
energy input = ivt where i is current = 6 A, v is volts = 140 and t time = 11 seconds
energy input = 6 × 140 × 11 = 9240 J
energy output = 0.64 × 9240 = 5913.6 J
510 pound-force = 2268.593 N
at height h, potential energy = mgh = 5913.6 J
2268.593 × h = 5913.6
h = 5913.6 / ( 2268.593) = 2.61 m