Respuesta :
more simply efficiency n=output work/input work =mgh/W(in)W(in) =18*9.81*0.5/0.90=98.1 Joule
Answer:
Input work: 93.2 J
Explanation:
The work efficiency formula is:
efficiency = output work/ input work
Solving for input work:
input work = output work/efficiency
The work required to lift an object is computed as follows:
Output work = mass * gravity * height
Using mass in kg, gravity in m/(s^2) and height in m; then work is expressed in Joules. Combining the equations and replacing with data, we get (units are omitted):
input work = 19*9.81*0.45/0.9 = 93.2 J
Note that 45 cm is equivalent to 0.45 m
