What is the Angular Momentum of Harry Potter on a Spinning Merry-Go-Round?

AI Thread Summary
Harry Potter, positioned 2.0 meters from the center of a spinning merry-go-round, has a mass of 50.0 kg and can endure an acceleration of up to 5g before losing consciousness. To determine his angular momentum at the point of passing out, the relevant equations are L = mvr and the relationship between centripetal acceleration (a = v^2/r). By equating the maximum acceleration (5g) to the centripetal acceleration, the velocity (v) can be calculated. Once v is determined, it can be substituted back into the angular momentum equation to find the magnitude of Harry's angular momentum. The discussion highlights the importance of understanding the relationship between acceleration, velocity, and angular momentum in this scenario.
bazookajason
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Homework Statement


Harry Potter is sitting 2.0 meters from the center of a merry-go-round when Draco Malfoy casts a spell that glues
Harry in place and then makes the merry-go-round start spinning on its axis. Harry has a mass of 50.0 kg and can
withstand 5:0 g's of acceleration before passing out. What is the magnitude of Harry's angular momentum when
he passes out?


Homework Equations


T=I alpha
L=mvr


The Attempt at a Solution



Assuming that the spell is a force then rF = I alpha. And using alpha = a/r, we using the max acceleration of 5g that
5mgr = Ia/r
However I'm not sure where to go from this, how do i get v? as time is unknwon
 
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bazookajason said:

Homework Statement


Harry Potter is sitting 2.0 meters from the center of a merry-go-round when Draco Malfoy casts a spell that glues
Harry in place and then makes the merry-go-round start spinning on its axis. Harry has a mass of 50.0 kg and can
withstand 5:0 g's of acceleration before passing out. What is the magnitude of Harry's angular momentum when
he passes out?

Lets look at the second eqn you mentioned,
L=mvr
you have m,r. what you need is v

Now, what do you think the acceleration 5g is acting along (direction)?
 
oh i see mv^2/r = ma a=5g :D
thanks!
 
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