How Is the Average Force on Water by a Turbine Blade Calculated?

AI Thread Summary
To calculate the average force exerted on water by a turbine blade, the change in momentum of the water must be considered. The water enters the blade at a velocity of +18.0 m/s and exits at -18.0 m/s, indicating a total change in velocity of 36.0 m/s. Given that the mass flow rate of the water is 75.0 kg/s, the average force can be determined using the impulse-momentum theorem. The force is calculated as the product of mass flow rate and the change in velocity. Understanding these principles is crucial for solving the problem accurately.
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Homework Statement


A stream of water strikes a stationary turbine blade, as the drawing illustrates. The incident water stream has a velocity of +18.0 m/s, while the exiting water stream has a velocity of -18.0 m/s. The mass of water per second that strikes the blade is 75.0 kg/s. Find the magnitude of the average force exerted on the water by the blade.

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Homework Equations


kinematics equations
(PEf - PE0)

The Attempt at a Solution


i have no idea where to start
 
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Think of impulse and change of momentum.

ehild
 

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