11. The largest helicopter ever built in the United States was the Sikorski CH-53E "Super Stallion". The four blades of its main rotors each has a radius of 24.1 m. If the rotors are turning at 50 rpm, what is the velocity at the tip of the blade? What is the acceleration? Give your answer for the acceleration both in m/s² and as a multiple of g.

11. The largest helicopter ever built in the United States was the Sikorski CH-53E "Super Stallion". The four blades of its main rotors each has a radius of 24.1 m. If the rotors are turning at 50 rpm, what is the velocity at the tip of the blade? What is the acceleration? Give your answer for the acceleration both in m/s² and as a multiple of g.

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter6: Uniform Circular Motion And Gravitation

Section: Chapter Questions

Problem 13PE: The propeller of a World War Il fighter plane is 2.30 m in diameter. (a) What is its angular...

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The propeller of a World War Il fighter plane is 2.30 m in diameter. (a) What is its angular velocity in radians per second if it spins at 1200 rev/min? (b) What is the linear speed of its tip at this angular velocity if the plane is stationary on the tarmac? (c) What is the centripetal acceleration of the propeller tip under these conditions? Calculate it in meters per second squared and convert to multiples of g.
One method of pitching a softball is called the wind-mill delivery method, in which the pitchers arm rotates through approximately 360 in a vertical plane before the 198-gram ball is released at the lowest point of the circular motion. An experienced pitcher can throw a ball with a speed of 98.0 mi/h. Assume the angular acceleration is uniform throughout the pitching motion and take the distance between the softball and the shoulder joint to be 74.2 cm. (a) Determine the angular speed of the arm in rev/s at the instant of release, (b) Find the value of the angular acceleration in rev/s2 and the radial and tangential acceleration of the ball just before it is released, (c) Determine the force exerted on the ball by the pitchers hand (both radial and tangential components) just before it is released.
In circular motion, a tangential acceleration can change the magnitude of the velocity but not its direction. Explain your answer.
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At its peak, a tornado is 60.0 m in diameter and carries 500 km/h winds. What is its angular velocity in revolutions per second?