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Los Frijoles

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## Homework Statement

A ball (mass M: 0.250kg) is attached to a rope (length l: 1.69m) that is fixed to a point somewhere. The ball is spinning in a circle around the support point so that the rope makes an angle 37 degrees from the vertical. I have to find the magnitude of the angular momentum of the ball about the support point, which I can't figure out for the life of me.

## Homework Equations

r = sin37l = 1.02m

F = Mg = 0.250kg * 9.8m/s^2

t (torque) = r x F = rFsin90 = 1.02m(.250)(9.8) = 2.49 Nm

..as for getting the angular momentum all I know is:

L = r x p = mvr (in this situation)

## The Attempt at a Solution

Part of the question was to get the torque, which after getting it wrong once and being shown the answer (and then given different data...that's how the computer grading this works) I figured out that where I was previously doing t = rFsin37 that it needed to be rFsin90 since it is from the perspective of the anchor point. After trying to reverse engineer the answer I got back for the angular momentum I have come up with nothing and I have no idea how to figure it out.

I think the problem lies in that I need to somehow transform torque into the tangential velocity v required for the equation for L and I can't find anywhere in my textbook where it says that and I can't seem to find any relating equations except t = dL/dt (and I don't have any dt (and I haven't yet completed my calculus course...yay :/...))

Can anyone help me figure this out?