9. Consider a 1-kg brick being whirled in a vertical circle at the end of 1-meter rope. a. What critical velocity must the brick achieve in order to pass safely through the top of its circular path? b. What is the tension in the rope as it is passing through the top of its circular path? How would the critical velocity of the brick be if it were to be whirled on the C. moon where the acceleration due to gravity is 1/6th that on earth?

9. Consider a 1-kg brick being whirled in a vertical circle at the end of 1-meter rope. a. What critical velocity must the brick achieve in order to pass safely through the top of its circular path? b. What is the tension in the rope as it is passing through the top of its circular path? How would the critical velocity of the brick be if it were to be whirled on the C. moon where the acceleration due to gravity is 1/6th that on earth?

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter7: Rotational Motion And The Law Of Gravity

Section: Chapter Questions

Problem 70AP: A 0.275-kg object is swung in a vertical circular path on a string 0.850 m long as in Figure P7.70....

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A number of amusement parks have rides that make loops like the one shown in Figure 6.33. For safety, the cars are attached to the rails in such a way cannot fall off. If the car goes over the top at just the right speed, gravity alone will supply the centripetal force. What other force acts and what is its direction if: (a) The car goes over the top at faster than this speed? (b) The car goes this speed? Figure 6.33 Amusement rides with a vertical loop are an example of a form of curved motion.
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A 0.275-kg object is swung in a vertical circular path on a string 0.850 m long as in Figure P7.70. (a) What are the forces acting on the ball at any point along this path? (b) Draw free-body diagrams for the ball when it is at the bottom of the circle and when it is at the top. (c) If its speed is 5.20 m/s at the top of the circle, what is the tension in the string there? (d) If the string breaks when its tension exceeds 22.5 N, what is the maximum speed the object can have at the bottom before the string breaks? Figure P7.70
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