The eggbeater wind turbine is stopped by us- ing spoilers which consist of 15 lbf blocks...

 

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The "eggbeater" wind turbine is stopped by us- ing spoilers which consist of 15 lbf blocks that slide out along the blades when the blades are turning. As the spoilers travel along the blade, they create a drag on the blade that slows and eventually stops the blade. If it is observed that the spoilers reach point A on the blade, deter- mine the minimum and maximum speed for the spoilers to maintain this position, and also the normal force magnitude they exert on the blade in each of these cases. The blade has the shape of a parabola in the vertical plane as shown in the figure. The coefficient of static friction be- tween the spoilers and the blades is p = 0.15. Hint: If the turbine is rotating about the y-axis, what is the path the spoiler will follow? What does this mean about the normal-tangential co- ordinate system of the spoiler? 20 ft 20 ft 10 ft- Figure 4: -y² = 400 A -20 ft- 20x -X The "eggbeater" wind turbine is stopped by us- ing spoilers which consist of 15 lbf blocks that slide out along the blades when the blades are turning. As the spoilers travel along the blade, they create a drag on the blade that slows and eventually stops the blade. If it is observed that the spoilers reach point A on the blade, deter- mine the minimum and maximum speed for the spoilers to maintain this position, and also the normal force magnitude they exert on the blade in each of these cases. The blade has the shape of a parabola in the vertical plane as shown in the figure. The coefficient of static friction be- tween the spoilers and the blades is p = 0.15. Hint: If the turbine is rotating about the y-axis, what is the path the spoiler will follow? What does this mean about the normal-tangential co- ordinate system of the spoiler? 20 ft 20 ft 10 ft- Figure 4: -y² = 400 A -20 ft- 20x -X