(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 200g object is tied to the end of a cord whirled around on top of a horizontal and frictionless table top in a 2.4 diameter circle at 3 rev/s. Determine a) the velocity of the object b)t he acceleration of the object and c)t he tension in the cord.

2. Relevant equations

Vc = (2*pi*r)/T

Ac = (Vc^2)/R

Fnet = MA

Ft - Fg =MAc

3. The attempt at a solution

So for A) I got Vc = (2*pi*1.2)(1/3) which equals 22.3 m/s

Then for B) I got Ac=(22.6)^2/(1.2) which equals 425.6 m/s

Now heres where I get lost

I tried doing this but it doesn't come out right...

Fnet = MA

Ft - Fg =MAc

Ft - 196.2 = (20)(425.6)

which means Ft = 8708.2N, I know the answer should be Force of tension = 85.1N, I'm not sure what I'm doing wrong.

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# Homework Help: Uniform Ciruclar Motion (whirling cord)

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