Calculate Angular Momentum of Falling Ball

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The discussion centers on calculating the angular momentum of a ball falling from a flagpole attached to a building. The initial formula presented for angular momentum is L = mrvsin(theta), but participants clarify that cosine should be used instead of sine due to the angle provided. There is confusion about whether the ball falls straight down or swings, impacting the interpretation of the problem. It is suggested that if the problem is viewed as determining the angular momentum relative to a point on the wall over time, the approach discussed may be valid. Clarification of the problem's context is deemed necessary for accurate calculations.
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A ball of mass m is fastened at the end of a flagpole connected to the side of a tall building at point P. The length of the flagpole is l and \theta is the angle the flagpole makes with the horizontal. The ball becomes loose and starts to fall. What is the angular momentum of the ball about point P?

so angular momentum is L=mrvsin(theta)

in this problem, the angle between force downwards and the radius is not given, but the angle beween the building and the radius is given. Therefore, sine cannot be used. Cosine must be used for this specific problem.

v=at
v=-gt

L=-mlgtCos\theta

is this the correct way to approach this question?
 
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I believe your description of this problem is lacking. I picture a ball that's fastened, and when it becomes unfastened it just falls straight down...
 
That's the way I interpreted the question as well. Do you perhaps mean that the flag pole becomes loose and swings down to hit the building? Perhaps then you may be looking for the angular momentum of the ball on the end of the pole...
 
I interpreted the problem similarly. Assuming the problem is "What is the angular momentum of the falling ball (with respect to a point on the wall) as a function of time?", then UrbanXrisis's answer is correct. (Maybe he can restate the problem.)
 
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