Question

In: Physics

A person of mass 74 kg stands at the center of a rotating merry-go-round platform of...

A person of mass 74 kg stands at the center of a rotating merry-go-round platform of radius 3.5 m and moment of inertia 880 kg⋅m2 . The platform rotates without friction with angular velocity 0.90 rad/s . The person walks radially to the edge of the platform.

Calculate the angular velocity when the person reaches the edge.

Calculate the rotational kinetic energy of the system of platform plus person before and after the person's walk.

Expert Solution

Solution:

Given the data

The mass of the person,

The radius of the marry-go-round,

Moment of inertia of the merry-go-round,

The initial angular velocity of the platform,

Let us consider the final angular velocity is

This we can get by using the law of conservation of angular momentum

Now, the initial and final rotational kinetic energy can be calculated as follows

This is the initial rotational kinetic energy of the system

The final rotational kinetic energy can be calculated as follows

genius_generous answered 2 years ago

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