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The mass of a pendulum bob is m = 2 kg and the length of the string is l . It is displaced through 90 ° from the vertical and released. What minimum tension (in N) should the string should be able to withstand so that it doesn't break during motion?

Correct answer

60

Step-by-step solution

Velocity at the lowest point, v = 2 g l At the lowest point, the tension in the string T = m g + m v 2 l = m g + m l 2 g l = 3 m g = 60 N

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