Solving the Water-Lifting Puzzle: An Analysis of Efficiency and Output

AI Thread Summary
The discussion focuses on calculating the amount of water a pump can lift from a river to arable land located 5.0 meters higher, using a pump with a power output of 1.0 kW, of which 65% is effective for lifting. The lifting work has been calculated as 39 kJ per minute. To determine how much water is pumped in that time, the energy used for lifting (650 J per second) is multiplied by 60 seconds to find the total energy available per minute. The energy required to lift a mass m of water to height h is expressed as mgh, allowing for the calculation of the mass of water lifted based on the energy available. The discussion emphasizes the relationship between energy, mass, and height in solving the water-lifting problem.
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A farmer uses a pump to lift water from a river to a arable land who lies 5.0m higher than the river. The pump exhaust an electrical effect of 1.0kW but only 65% is used to do the lifting. ok A) I have resolved the lifting work is 0,65*60 = 39kJ

But B) is harder,,,, how much water is pumped up during a minute ...?

I have no idea how to solv this please help me
 
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In A) you've apparently solved how much work is used to lifting the water a minute.
During this minute, how much water is lifted?
Is the anwer in kg or m3? Doesn't really matter, you know their relation.

What is the energy required to lift a ball of mass m to height h?
 
You know that 65% of the pumps power (1 kW) is used to lift water.
This means that every second, 650 J of energy is used by the pump to list water, multiply by 60 to get energy per minute.
You know how much energy it will take to lift m kilograms of water h distance up against gravity g (mgh), since in this problem h and g are givens/constants, so just solve for m.
 
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