Calculating Time to Lift 300kg Piano 10 Meters with 400 Watts Power

[PhunWithPhysics]

I have a 300 kg piano being lifted at a steady speed from the ground to a hieght of 10 meters and the crane that is doing the lifting is providing 400 watts of power. How much time does it take to get the piano to the top.
So far I have Power = work/Time
so time is Work/ power , so, work is equal to mass X gravity X hieght
so I have (300)(9.8)(10)/(400) = 73.5 sec...is this correct...any help would be nice. Thanks

 

[Diane_]

For the information you have, it looks fine, although you'll want to check the significant digits.

It is, of course, an underestimate - do you see why?

 

[quicknote]

Your calculation is correct. To lift the piano, work needs to be done against the force of gravity. The amount of work done is equal to the mass of the piano multiplied by the acceleration due to gravity (9.8 m/s^2) and the height it is being lifted (10 meters). This work is being done by the crane, which provides a power output of 400 watts. Using the equation Power = Work/Time, we can rearrange to solve for time, giving us Time = Work/Power. Plugging in the values for work and power, we get Time = (300 kg)(9.8 m/s^2)(10 m)/(400 watts) = 73.5 seconds. This means it would take approximately 73.5 seconds for the piano to be lifted to the top. It is important to note that this calculation assumes ideal conditions and does not take into account factors such as friction or any potential inefficiencies in the crane's power output.