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deuce123
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Homework Statement
A 220-kg beam 2.8 m in length slides broadside down the ice with a speed of 23 m/s . A 68-kgman at rest grabs one end as it goes past and hangs on as both he and the beam go spinning down the ice. Assume frictionless motion. (Figure 1)
Homework Equations
L1=L2
Iω=L
The Attempt at a Solution
With what angular velocity does the system rotate about its cm? For this question i tried to use the initial moment of inertia w.r.t the CM by...[ 1/12Ml^2 + Mh^2] ω------ where l=2.8m M=220kg and h=.33m ----- For some reason this doesn't work. I'm positive the other side of the equation i listed is correct, i had it checked out. I ended up getting the answer for this question too see where i went wrong, it ended up being ω=6.8 rad/s--- And they used (Mhv)
M=220kg h=.33m v=23 m/s. I'm not sure how that equates too being angular momentum (Iω), but it worked for the answer. Can someone explain to me why they used that and why it worked. Also how else can you approach the initial angular momentum, somewhere along the lines of what i was doing. Thank you,