Type of curvature of gradient force from edge to center of a sphere

1. Jun 5, 2013

Sedemichra

I was doing some simple physics with a ball resting on a table and I made this curve

(0,0) (25, 6.8) (50, 27.51) (75, 63.4) (100, 112.34) (125, 175.7) (150, 253.3) (175, 345.4)

I was wondering if anyone could identify what sort of curve it is? I am just curious.

This is not a homework problem.

2. Jun 5, 2013

ZapperZ

Staff Emeritus
Why can't you plot this out, post it here, and tell us what you think?

Zz.

3. Jun 5, 2013

Sedemichra

I got the points off of a curve that developed due to the the apparent force of gravity pushing a sphere down on a table...I cant tell if it is hyperbolic or parabolic...or maybe a section of an ellipse(if thats even different)...I have seen the curve and I am guessing it is a parabola but I am not sure how to be certain because I could do a quadratic regression in my calculator but that wouldnt really prove anything would it?

4. Jun 5, 2013

Sedemichra

Here is a picture of the curve

Hyperbole, Parabola, or a section of ellipse I cant tell the difference

5. Jun 5, 2013

Khashishi

I did a curve fit on Excel
The ordered pairs you gave at the beginning lie very close to a perfect parabola:
y = 0.011329238095238*x^2 - 0.009373809523815*x - 0.037083333332703
with R^2 of 0.999997

6. Jun 5, 2013

Sedemichra

Thanks man, I wonder why the force over the gradient of the circle translates proportionally into a practically perfect parabola?

I will have to do some more investigating!