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## Homework Statement

I'm currently working on a lab which involves swinging a bung in the horizontal plane (just like a conical pendulum), however I'm a bit stumped at finding air resistance.

The variables we know are the radius, the centripetal force and the velocity of the bung.

## The Attempt at a Solution

In attempt to calculate the wind resistance, i did the following:

W (non conservative) = delta KE +delta PE

Force (of air resistance) x distance = KE (theoretical) - KE (Experimental)

If i plotted KE theoretical and KE experimental on the y-axis and radius on the x, there is a gap inbetween both series, a gap that gets wider as velocity increases. This makes sense because velocity is proportional to force. And here i yield difference of 0.5 to 0.7.

HOWEVER, according to: Force (of air resistance) x distance = KE (theoretical) - KE (Experimental)

if i divide both sides by distance (2 pi radius: the conical pendulumn travles in a circle) and when i plot the force of air resistance over radius, air ressistance seems to go down as r increased! but this can't be the case because for some constant centripetal force, r is proportional to velocity SQUARED, and velocity is proportional to the force of air resistance.

So what did i do wrong??

thanks