Understanding Centripetal Force in a Rubber Ball and String Lab

[pisces93]

Homework Statement

I did a lab where there was a glass tube with a rubber ball attached and a string hanging from the glass tube with metal washers attached at the bottom.

My question is if the ball were to hang too low why would the centripetal force be less accurate is it because there is less force when hanging to low, and if i were to maintain a given radius and velocity what would happen to the material.

 

[gneill]

Did you draw free body diagrams for the two cases? If not, you might wish to do so and compare the relative magnitudes of the forces involved (particularly for the ones you're interested in measuring and those you want to minimize or maximize).