Angular Momentum of a candy dish

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SUMMARY

The discussion centers on calculating the angular speed (ω) of a lazy susan, a uniform disk with a mass of 0.876 kg and a radius of 0.244 m, when a bug of mass 35.9 g walks along its edge at a speed of 6.12 cm/s. The conservation of angular momentum is the key principle applied here, where the total angular momentum of the system (bug and disk) remains constant. The participants emphasize the need to calculate the angular momentum of both the bug and the disk to find the resulting angular speed.

PREREQUISITES
  • Understanding of angular momentum and its conservation
  • Familiarity with the moment of inertia for a uniform disk
  • Basic knowledge of rotational motion equations
  • Ability to perform unit conversions (e.g., from grams to kilograms)
NEXT STEPS
  • Calculate the moment of inertia for a uniform disk using the formula I = 0.5 * m * r²
  • Learn how to apply the conservation of angular momentum in rotational systems
  • Explore the relationship between linear velocity and angular velocity
  • Practice similar problems involving rotating systems and external forces
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Students studying physics, particularly those focusing on mechanics and rotational dynamics, as well as educators looking for practical examples of angular momentum conservation.

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Homework Statement


A candy dish that rotates is called a lazy susan. This lazy susan is a uniform disk (mass 0.876 kg, radius 0.244 m), rotating about the center of the disk on a frictionless bearing. Suppose a large bug of mass 35.9 g sits at rest at on the edge of the empty lazy susan, which is initially at rest. The bug now begins to walk along the circumference of the disk at 6.12 cm/s relative to the disk. Find ω, the angular speed of the lazy susan.


Homework Equations



I just need a hint... based on the information provided i think i need to work my way through the conservation of angular momentum.. ... any suggestion

The Attempt at a Solution

 
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Conservation of angular momentum is indeed the way to go.

In this case what must the total angular momentum of the system (bug and disc) be?

What is the angular momentum of the bug?

Therefore, what must be the angular momentum of the disc?
 

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