A simple pendulum is constructed using a string 85 cm long and a ball having a mass of 50

grams. At a certain location near the surface of the earth, the ball makes 20 vibrations in

38 seconds as it swings along a 5 cm arc. At the same location, how many vibrations will a

100-gram ball make in a time of 1 minute if the length of the string is 60 cm and the arc of

swing is 10 cm?

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