Moment of Inertia and Angular Velocity

AI Thread Summary
The discussion revolves around a physics problem involving a student spinning while holding a textbook, focusing on the relationship between moment of inertia and angular velocity. Participants emphasize the importance of conservation of angular momentum in solving the problem. Initial confusion about calculating the moment of inertia is expressed, particularly regarding the radius and mass. Ultimately, the student resolves the issue with assistance from others in the forum. The conversation highlights the collaborative nature of problem-solving in physics.
primeboss
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Homework Statement


A student hold a 2.0 kg textbook to their chest as they spin at an angular velocity of 6 rad/sec. Assuming the mass moment of inertia of the student to be 1.4 kgm^2, what is the angular velocity if the student hold the book 0.7 meters away

Homework Equations


The Attempt at a Solution


I do not know where to start. i can find a correlation with angular velocity and moment of inertia. Also do i use energy?
 
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welcome to pf!

hi primeboss! welcome to pf! :smile:

momentum and angular momentum are always conserved :wink:
 
Thanks for the reply, but i am still confused into how to approach the problem
 
uhh? :redface: use conservation of angular momentum …

what do you get?​
 
"I don't see how i can find the intial momentum of inertia, since i do not know the radius but only the mass"

edit:NEVERMIND i got it. Thanks for all your help.
 
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