Angular momentum and orbital angular momentum problems

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Homework Help Overview

The discussion revolves around problems related to angular momentum and torque, specifically involving a proton in a cyclotron, changes in angular momentum, and the characteristics of a pulsar. The subject area includes concepts from rotational dynamics and astrophysics.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants explore various aspects of angular momentum, including calculations for a proton's orbital angular momentum and the average torque on an object. There are attempts to relate the pulsar's properties to its linear speed and rotational period. Some participants express uncertainty about the material covered in their physics class and seek clarification on specific formulas.

Discussion Status

Some participants have made progress on specific questions, with one indicating they have a potential solution for question 3a. Others are seeking guidance on how to approach the problems, and there is a general exploration of the relevant equations and concepts without a clear consensus on the solutions.

Contextual Notes

Participants mention that the topics are not covered in their physics class, indicating a reliance on independent study. There is also a side question regarding profile customization that is unrelated to the main discussion.

sebasalekhine7
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1. A proton of mass rotates with an angular speed of 2*10^6 rad/s in a circle of radius 0.8m in a cyclotron. What is the orbital angular momentum of the proton?

2.An object's angular momentum changes by 10Kgm/s^2. What magnitude average torque acted on this object?

3. A pulsar which emits radio waves 642 times per second has a mass of 2*10^30 kg and has a radius of only 15km.
a) What is the linear speed of a point on the equator of this pulsar? Ignore relativistic effects.
b) If our sun, with mass 2*10^30 kg and radius 7*10^5 km had the same angular momentum as this pulsar, approximately what would its rotational period be?

BTW, how do I upload an avatar to my profile? I tried in the CP but I didn't find any option that would allow me to do so.
 
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I understand what you mean by your post, but I have little to work with, since we are not having these topics in our physics class, this is independent study for the science league. Let's see, I have [tex]I=2/5MR^2[/tex] , I also have [tex]\omega=v/r[/tex]

I think 3a is like this: Ok, I think I have 3a. it is rotating at [tex](642rev/s)(2\pi rad/rev)(15000m)=V[/tex]

Besides this, I have no idea as to what to do next.
 
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Ok, I think I've got question # 1. Is orbital angular momentum =angular velocity*radius^2 ?
 
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