Concept explainers
Suppose that the speed of a ball moving in a horizontal circle is increasing at a steady rate. Is this increase in speed produced by the centripetal acceleration? Explain.
Whether the increase in speed of the ball moving in horizontal circle is produced by the centripetal acceleration.
Answer to Problem 1CQ
The increase in the speed of the ball moving in horizontal circle is not produced by the centripetal acceleration.
Explanation of Solution
Centripetal acceleration is the rate of change in velocity of an object that is associated with the change in direction of the velocity. It is always perpendicular to the velocity vector itself and toward the center of the curve.
The centripetal acceleration is directly proportional to the square of the speed of the object and inversely proportional to the radius of the curve. There must be a force acting on the object to produce the centripetal acceleration.
In the given situation, speed of the ball moving in the horizontal circle is increasing. But centripetal acceleration is associated with change in direction of the velocity vector and not the change in magnitude of the velocity vector or speed.
Conclusion:
Thus the increase in the speed of the ball moving in horizontal circle is not produced by the centripetal acceleration.
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Chapter 5 Solutions
Physics of Everyday Phenomena
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