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

A mass moves in a circular path that has a radius of 24.6cm on a horizontal frictionaless surface. If the centripetal force acting on the mass is 96.5N, what is the kinetic energy of the mass?

r=0.246m

F_{c}=96.5N

2. Relevant equations

He told us to use these and "play around with them":

F_{c}=mv^{2}/r

E_{k}=0.5mv^{2}

3. The attempt at a solution

I have not a clue as to how to even begin this one. Maybe use the idea that acceleration centripetal=force centripetal(minus mass)? So use:

a_{c}=v^{2}/r

96.5N=v^{2}/0.246m

v^{2}=392m/s

v=19.8m/s

F_{c}=mv^{2}/r

96.5N(0.246m)=m(19.8m/s)^{2}

m=0.0605kg

E_{k}=0.5mv^{2}

E_{k}=0.5(0,0605kg)(392m^2/s^2)

E_{k}=11.9J

Or am I completely and irrevocably lost?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Kinetic Energy of a mass moving in horizontal circle

**Physics Forums | Science Articles, Homework Help, Discussion**