Solve rpm in rotational motion problem

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SUMMARY

The discussion focuses on calculating the required revolutions per minute (rpm) for a centrifuge to achieve a radial acceleration of 100,000 g's at a distance of 7.0 cm from the axis of rotation. The initial calculations yielded an angular velocity of approximately 3,741 radians per minute, which was then converted to 35,723 rpm after accounting for the conversion from radians to revolutions. The final answer aligns closely with the textbook's value of 36,000 rpm, confirming the accuracy of the calculations. Key equations utilized include radial acceleration and the relationship between linear and angular velocity.

PREREQUISITES
  • Understanding of radial acceleration and its formula: radial accel = v^2/r
  • Familiarity with angular velocity and its relationship to linear velocity: v = rw
  • Knowledge of unit conversions between radians and revolutions
  • Basic algebra skills for solving equations
NEXT STEPS
  • Study the derivation of the radial acceleration formula in rotational motion
  • Learn about angular velocity and its applications in physics
  • Explore unit conversion techniques between different angular measurements
  • Investigate real-world applications of centrifuges in laboratory settings
USEFUL FOR

Students in physics, particularly those studying rotational motion, as well as educators and anyone involved in laboratory equipment design and analysis.

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Homework Statement


How fast (in rpm) must a centrifuge rotate if a particle 7.0 cm from the axis of rotation is to experience an acceleration of 100,000 g's?

My variables
radius= 7 cm or .07m
radial accel= 100,000 g's or 980,000m/s^2 or 98,000,000cm/s^2
V= I think I need this to get w
w= ? I think I need to solve this to get rpm
rpm= ? this is what I want


Homework Equations


radial accel = v^2/r
v= rw


The Attempt at a Solution


980000/.07 = 68,600


[tex]\sqrt{}68600[/tex]/.07= 261.9
261.9/.07 = 3,741 rpm

whether i set everything as meter or centimeter, I still get the same answer. I check the back of the book and it says 3.6x10^4 or 36,000rpm

Homework Statement




Any help would be appreciated.
 
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Your answer is correct but it's in radians per second. rpm is revolutions per minute. A revolution is 2*pi radians and a minute is 60 seconds. Can you convert it to rpm?
 
thank you, I did:
3741rad*60=224,460
224,460/2*pi=35,723rpm or 36000rpm if I round up. Thanks again!
 

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