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Artificial Gravity

  • Thread starter Momentum09
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  • #1
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"Artificial Gravity"

Homework Statement



A space station in the form of a large wheel, 333m in diameter, rotates to provide an "artificial gravity" of 9m/s^2 for people located on the outer rim. Find the rotational frequency of the wheel that will produce this effect. Answer in units of rpm [revolutions per minute]

Homework Equations



w = 2pi/T , Frequency = 1/T

The Attempt at a Solution



I first equated the normal force with the centripetal force, which is mg = mv^2/r. Cancelling out the m, I got gr = v^2. After I solved for V, I plugged it into the w = 2pi/T equation to find T, then 1/T. To convert the answer to rpm, I multiplied what I got for F by 60 and divided by 2pi. However I kept getting the wrong answer. Can someone please help? Thank you!
 

Answers and Replies

  • #2
hage567
Homework Helper
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After I solved for V, I plugged it into the w = 2pi/T equation to find T
How did you relate v to w when finding T in this step?

Be sure to keep track of the units to make sure things make sense.

What answer did you get?
 
  • #3
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I got 3.487429162 rpm
 
  • #4
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I also know that w = 2 x pi x frequency
 
  • #5
hage567
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Yes, but remember that v is linear velocity, and w is angular velocity. They are not interchangeable. Do you know the relation between those two quantities?
 
  • #6
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I know that w = v/r
 
  • #7
hage567
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So what do you get if you make use of that? You found what v is, and ultimately what you want to find is w (in rev/min).

You're initial approach is OK, it's just the long way around. But you still need to use v=rw.
 
  • #8
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oh! I got it now! Thank you so much!
 
  • #9
hage567
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You're welcome. :smile:
 

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