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Underground water is to be pumped by an 78% efficient 5-kw submerged pump to a pool whose free surface is 30 m above the underground water level. the diameter of the pipe is 7 cm on the intake side and 5 cm on the discharge side. take the density of water to be 1 kg/l = 1000 kg/m3. assume the elevation difference between the pump inlet and the outlet and the effect of the kinetic energy correction factors to be negligible. note: this is a multi-part question. once an answer is submitted, you will be unable to return to this part.

User Lesleh
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Final answer:

The question revolves around the use of Bernoulli's principle and the continuity equation to calculate the necessary pressure a pump must supply to raise water through a pipeline to a specific height with a given flow rate, taking into account the efficiency of the pump.

Step-by-step explanation:

Calculating the Required Pump Pressure in Fluid Mechanics

The question presented involves determining the necessary pump pressure to elevate water through a pipeline with a specified flow rate and elevation gain. Using Bernoulli's principle and the continuity equation, we can conclude that the key factors influencing the pressure output are the height to which the water must be pumped and the flow rate of the water.

In these scenarios, gravitational potential energy plays a considerable role, as the pump must work against the force of gravity to raise the water to a certain height. The efficiency of the pump is also taken into account, which indicates how much of the electrical energy used is converted into work for moving the water.

To calculate the pressure needed at the lower end of the pipeline to achieve the desired flow rate at the upper end, you would use Bernoulli's equation considering the elevation change, dynamics of the fluid, and the efficiency of the pump. We can simplify the pressure calculation by assuming the velocity at the intake is negligible, ignoring the kinetic energy correction factors, and focusing on the difference in elevation and flow rate.

User Pavan Garre
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