Rotational motion inelastic collision

AI Thread Summary
The discussion centers on a physics problem involving a totally inelastic collision between a ball of clay and a rotating disk. Participants are attempting to calculate the final angular speed of the combined system after the collision, considering both a direct tangential impact and an impact at a 30° angle. Key equations related to conservation of momentum and angular momentum are referenced, but there is uncertainty about their application. The conversation highlights the importance of understanding physical laws governing motion, particularly those related to angular momentum. Overall, the thread emphasizes the need for clarity in applying physics principles to solve the problem accurately.
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Homework Statement



A ball of clay of mass m travels with velocity v in a path tangent to a disk of radius R and mass M. The clay collides with the disk tangentially to its outer rim ( a totally inelastic collision) and the clay and disk begins to spin about the axis.
a) What is the final angular speed of the clay and disk ( don't forget to include the mass m after the collision.
b) if the clay had collided with the rim at an angle of 30° to the tangent line what would the final angular speed be then

Homework Equations



v'b=v'a
va=v'acosθ+v'bcosθ

The Attempt at a Solution



a)
mva=mv'acosθ+mv'bcosθ
0=mv'asinθ+mv'bsinθ

v'b=-va(sinθ/sin(-θ))
v'a=v'b
=va/2cosθ

b) I am not sure without knowinif the formula above is correct
 
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If you are unsure about a formula - try using physics.
What are the laws that the motion has to follow?
 
what do u mean? Newtons law?
 
You know a whole bunch of physical laws besides Newton's ones.
How many do you know that concern angular momentum and momentum?
 

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