Rotational velocity of a system that has a mass launched at it stick to it

AI Thread Summary
A clay mass of 0.74 kg strikes a 1.90 kg bar perpendicularly on a frictionless table, sticking to it and causing the system to rotate about its center of mass. The center of mass is calculated to be at 0.6486 m from the bar's end, and the moment of inertia is determined to be 2.34 kg·m². Using the conservation of angular momentum, the initial momentum of the clay (0.74 kg moving at 6.8 m/s) is set equal to the rotational momentum after the impact. The calculated angular speed of the bar/clay system is 2.15 rad/s. The discussion emphasizes the importance of applying conservation of angular momentum correctly in such problems.
ttk3
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Homework Statement


On a frictionless table, a glob of clay of mass 0.74 kg strikes a bar of mass 1.90 kg perpendicularly at a point 0.48 m from the center of the bar and sticks to it. If the bar is 1.50 m long and the clay is moving at 6.8 m/s before striking the bar, at what angular speed does the bar/clay system rotate about its center of mass after the impact?


Homework Equations


displacement of center of mass = m1x1 + m2x2 \ m1 + m2
Ip = Icm + md^2
mVo = IW


The Attempt at a Solution



displacement of center of mass = 1.90*.48 / .74 *.190
= .6486

Ip = 1.90(.75^2) + (.74+1.90)(.48)
= 2.34

mcVo = IW
.74(6.8) = 2.34 W
= 2.15 rad/s
 
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ttk3 said:

Homework Statement




Homework Equations


displacement of center of mass = m1x1 + m2x2 \ m1 + m2
Ip = Icm + md^2
mVo = IW


I think u should check the last equation. Furthermore, please apply conservation of angular momentum carefully.
 
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