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Question
A heavy mass is attached to a thin wire and is whirled in a vertical circle. The wire is most likely to break
Options
when the mass is at the highest point
when the mass is at the lowest point
when the wire is horizontal
at an angle of cos−1(1/3) from the upward vertical.
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Solution
If the velocity of the mass is a maximum at the bottom, then the string experiences tension due to both the weight of the mass and the high centrifugal force. Both these factors weigh the mass downwards. The tension is therefore, maximum at the lowest point, causing the string to most likely break at the bottom.
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