Kinetic Energy of a mass moving in horizontal circle

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SUMMARY

The discussion centers on calculating the kinetic energy of a mass moving in a horizontal circle with a radius of 24.6 cm and a centripetal force of 96.5 N. The participant correctly derived the mass as 0.0605 kg and calculated the kinetic energy (Ek) to be 11.9 J using the equations Fc = mv²/r and Ek = 0.5mv². The solution involved manipulating the equations to find the velocity and subsequently the kinetic energy, confirming the accuracy of the calculations through teacher validation.

PREREQUISITES
  • Understanding of centripetal force (Fc) and its formula: Fc = mv²/r
  • Knowledge of kinetic energy (Ek) and its formula: Ek = 0.5mv²
  • Ability to manipulate algebraic equations to solve for unknown variables
  • Familiarity with units of measurement in physics (e.g., Newtons, kilograms, meters)
NEXT STEPS
  • Study the relationship between centripetal acceleration and velocity in circular motion
  • Explore the concept of energy conservation in mechanical systems
  • Learn about the implications of frictionless surfaces on circular motion
  • Investigate real-world applications of kinetic energy in rotational dynamics
USEFUL FOR

Students studying physics, particularly those focusing on mechanics and circular motion, as well as educators seeking to reinforce concepts of kinetic energy and centripetal force.

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Homework Statement


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
Fc=96.5N


Homework Equations


He told us to use these and "play around with them":
Fc=mv2/r
Ek=0.5mv2



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:
ac=v2/r
96.5N=v2/0.246m
v2=392m/s
v=19.8m/s

Fc=mv2/r
96.5N(0.246m)=m(19.8m/s)2
m=0.0605kg

Ek=0.5mv2
Ek=0.5(0,0605kg)(392m^2/s^2)
Ek=11.9J

Or am I completely and irrevocably lost?
 
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This has been staring me in the face for a while...

I now think I have the solution. Look at your two equations, and look what they have in common. Once you find one, you can use it to find the Kinetic Energy of that mass. Good Luck!
 
Just to update, I got that question correct. In the solution the teacher showed us, he combined the two formulas and got the same answer.
 

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