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### I-'m not sure the correct answer to this question- 14- A 2 m radius 10.docx

1. I'm not sure the correct answer to this question. 14. A 2 m radius 100 kg disk-shaped merry-go-round is turning at 1.5 rad/s with a 50 kg child on the rim. The child throws at 10 kg medicine ball in the direction of rotation at 10 m/s. What is the rotational speed of the merry-go-round after the medicine ball leaves the kid's hands? a) 1.15 rad/s b) 1.25 rad/s c) 1.35 rad/s d1.45 rad's e) 1.55 rad/s Solution here, radius , r = 2 m mass of merry-go-round , m1 = 100 kg mass of child , m2 = 50 kg mass of medicine ball , m3 = 10 kg v = 10 m/s w0 = 1.5 rad/s let the rotational speed be w using conservation of angular momentum (0.5 * m1 * r^2 + m2 * r^2 + m3 * r^2) * w0 - m1 * r * v = (0.5 * m1 * r^2 + m2 * r^2) * w ( 0.5 * 100 * 2^2 + 50 * 2^2 + 10 * 2^2) * 1.5 - 10 * 2 * 10 = ( 0.5 * 100 * 2^2 + 50 * 2^2) * w solving for w w = 1.15 rad/s the angular speed is a) 1.15 rad/s