How Does a Rotating Ball Affect Force Directions in a Box?

AI Thread Summary
The discussion focuses on the forces exerted by a rotating ball inside a box placed on a sensitive scale. When the ball rotates clockwise, the direction of the force exerted on the box varies based on the ball's position: at 12 o'clock, the force is directed upwards; at 3 o'clock, it shifts to the left; at 6 o'clock, it points downwards; and at 9 o'clock, it moves to the right. The analysis assumes a fixed axle of rotation and that the vibration is solely due to the ball's rotation. Additionally, the total force on the scale would include both the centripetal force and gravitational force. Understanding these dynamics is crucial for analyzing the effects of rotation on force directions.
CJK
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Hello,
I have a question about force produced by rotating ball.
Let's say the ball rotates clockwise.
The rotating ball is attached to the rotation axis with a rigid rod.
The rotating ball is placed inside of the box.
The box is placed on the very sensitive scale.
The box is vibrating.
I would like to know the direction of the force F exerted on the box at each of the following ball positions:
Ball is a 12 o'clock
Ball is a 3 o'clock
Ball is a 6 o'clock
Ball is a 9 o'clock

What would scale show in terms of direction of force F for each of the above positions?

Thanks
 
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Your question is not entirely clear. I'll make these assumptions:
The axle of rotation is fixed to the box.
Some mechanism is forcing the ball to rotate around the axle at constant rate.
The vibration is a result of this, not of any additional forces.
The rotation is in the vertical plane.

Ignoring gravity, the force exerted by the ball on the axle (and thence on the box) is the reaction to the centripetal force. At 12 o'clock the force is upwards, at 3 o'clock to the left, etc. Just add the gravitational force for the total.
 
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