How Do You Calculate Angular Momentum for a Ball on a String?

AI Thread Summary
To calculate the angular momentum of a ball on a string, first identify the forces acting on the ball and draw a free-body diagram. The ball's mass is 1.9 kg, and it moves in a horizontal circle with a string length of 1.8 m at an angle of 30° from the vertical. The horizontal and vertical components of angular momentum can be determined by analyzing the motion and forces, particularly focusing on the tangential and angular speeds. Understanding the relationship between these forces and the ball's motion will aid in solving the problem. This approach will lead to the calculation of the angular momentum and its components.
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Homework Statement



A 1.9 kg ball attached to a string whose length is 1.8 m moves counterclockwise (as viewed from above) in a horizontal circle (see figure below). The string makes an angle θ = 30° with the vertical.
(a) Determine both the horizontal and vertical components of the angular momentum of the ball about the point of support P. (Use variables w,t and directions i, j, and k as necessary.)
horizontal 1
vertical 2

(b) Find the magnitude of d/dt.
3 N*m


Homework Equations



the equations is what I am trying to solve for.

The Attempt at a Solution


I have no idea how to attempt solving this equation :(
 
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Do a free-body diagram.

What are the forces acting on the ball. Draw them as vectors. What do all the forces add up to?

How is that result related to the tangential or angular speed of the ball?

When you get that far, you may be able to solve the rest.

AM
 

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