Question

Problem 9: A playground merry-go-round with a mass of 150 kg and a radius of 1.8 m is rotating with a frequency of 0.58 rev/s. Randomized Variables m 150 kg 1m2 19kg ωǐ_ 0.58 revs What is the magnitude of its angular velocity, in radians per second, after a 19 kg child gets onto it by grabbing its outer edge? The child is initially at rest. Numeric :A numeric value is expected and not an expression. or

Answer 1

using conservation of angular momentum

I w1 = ( I +m r^2) w2

0.5 * 150* 1.8^2* 0.580= ( 0.5* 150* 1.8^2 + 19* 1.8^2)* w2

w2 = 0.463 rev/s = 2.907 rad/s

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