Uniform Circular Motion Question

AI Thread Summary
A body with a mass of 81.7g is moving in a circular path with a radius of 0.65m, experiencing a centrifugal force of 0.35N. The relevant equations for circular motion were provided, including those for acceleration and period. The initial calculations led to a velocity of approximately 0.5276 m/s and a period of revolution of about 7.736 seconds. However, the solution was deemed incorrect, possibly due to rounding errors or unit conversion issues, as the mass should be converted to kilograms. It’s emphasized that attention to units is crucial in these calculations.
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1. Homework Statement :
A body of mass 81.7g is moving in a circular path of radius 0.65m. If we calculate the centrifugal force on it to have a magnitude of 0.35N, what is the period of revolution? (2 decimals, UNITS!)(p = 3.14)


2. Homework Equations :
I'm given the following equations:
a = v^2/r
v = Circumference/Period = 2pi/T
a = 4pi^2r/T^2
F = Mg
F = ma
3. The Attempt at a Solution :
I took .35 = mv^2/r so .35 = 81.7v^2/.65 so v = .5276
then I took T = 2pir/v so T = 2pi(.65)/.5276 so T =7.736

I got this wrong when I entered it. I may have rounded wrong at the end or didn't do it right in the first place Any help would be appreciated.
 
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The supplied mass is in grams.
 
so I would divide the mass by 1000 then do what i did?
 
Seems that way. Always take note of the units in questions and remember that standard formula are for SI units.
 
Yes. The S.I. unit of mass is kilograms.
 
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