1.) A playground merry-go-round with a radius of 1.75 m and a rotational inertia of 124.5...

1.) A playground merry-go-round with a radius of 1.75 m and a rotational inertia of 124.5 kgm² is stationary. A robot with a mass of 32.5 kg gets on and walks around the edge of the merry-go-round. How many revolutions around the merry-go-round must the robot make in order for the merry-go-round to make two full revolutions?

2.) A student has an idea for a special record player that uses no electricity. The base is a circular turntable that floats on small jets of air after being set in motion such that it spins with no friction. This disk-like turntable has a mass of 3.70 kg and a radius of 37.0 cm. The student gives it a quick push in the clockwise direction such that it is freely spinning at an angular speed of 23.0 revolutions per second. A smaller circular record has a radius of 19.0 cm and a mass of 1.90 kg. This record is not rotating when it is suddenly dropped straight down onto the turntable so that the axis of rotation passes through the center of the record (as shown). Assume the rotational inertia for a uniform circular disk can be found as (1/2) MR². What is the final angular speed of this record and freewheeling turntable?

Expert Solution

genius_generous answered 2 years ago

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