How Does Mud Impact the Angular Velocity of a Pivoted Meter Rule?

AI Thread Summary
The discussion centers on the impact of a 20g piece of mud traveling at 5 m/s on the angular velocity of a pivoted meter rule. The initial angular velocity is calculated using the formula for angular momentum, resulting in an answer of 2.5 rad/s. Participants emphasize the importance of using consistent units in calculations, specifically converting to meters, kilograms, and seconds. There is a moment of confusion regarding the correct answer, with one participant mistakenly believing the answer was 5 rad/s. The conversation highlights the need for careful consideration of assumptions in physics problems.
Harmony
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A metre rule is freely pivoted about its centre. A piece of mud of mass 20g traveling at 5ms-1 strikes and sticks to one end of the rule so that the rule starts to rotate in a horizontal circle. If the moment of Inertia of the rule and the mud about the pivot is 0.02kgm^2, the initial angular velocity of the rule is...(Answer:2.5rads-1)

I have made assumption that the momentum of the mud is transfer solely to
the angular momentum. (mv=Iw)
I got the answer 5 rads-1, obviously wrong. I believe that my assumption is wrong. How should I attempt this question?
 
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mks units

hi harmony

make sure you convert all units to m-> meters, k-> kilograms, and s-> seconds...then you should get the correct answer with your assumption.

ahhh actually I am wrong i was reading your post backwards. i thought 5 rad/s was the correct answer...gonna have to think about this for a little while

gabe
 
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