Homework Task: Find the power of water

AI Thread Summary
To find the power of water falling from a height of 20 meters, the mass of the water must first be calculated, which is 80,000 kg for 80 m³. This mass translates to a force of 784,000 Newtons (using W = mg). The power can then be determined using the formula P = Fv, where the velocity can be derived from the height and time. Since the water falls 80 m³ per minute, converting this to seconds gives a flow rate of approximately 1,333.33 kg/s. Ultimately, the power of the falling water can be calculated based on these values.
besfort
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Homework Statement


Find the power of the water if it falls from the height (h= 20m), for every minute falls 80m^3 (Volume=80m3).


Homework Equations


P=A/t
W = mg
A = Fh
P= Fv


The Attempt at a Solution


I attempted to find the mass first, but I couldn't find any formula to do so.
 
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besfort said:

Homework Statement


Find the power of the water if it falls from the height (h= 20m), for every minute falls 80m^3 (Volume=80m3).


Homework Equations


P=A/t
W = mg
A = Fh
P= Fv


The Attempt at a Solution


I attempted to find the mass first, but I couldn't find any formula to do so.

1cc of water weighs 1 gram. So a liter of water weighs a kilogram. That should get you to the answer.
 
If 80m^3 = 80000l, then that means the mass is 80000kg, aye?
 
besfort said:
If 80m^3 = 80000l, then that means the mass is 80000kg, aye?

Right so you have 80,000 kg falling per minute. How much kg per second is that? Hence how much Newtons per second is that?

Remember that Power = Rate at which work is done = Force*distance/Time
 
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