1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Circular Motion - Quick Help Please!

  1. Oct 18, 2005 #1
    Andy and Bella move in circular paths about a common point with the same constant angular velocity [tex]\omega[/tex]. Bella's mass is half the mass of Andy. The distance, where Andy is from the centre of the circle, is twice the distance of Bella. Who of the two will experience the greater magnitude of the centripetal force, [tex]F_c[/tex]?

    The answer given is that they will experience the SAME force. However, I found otherwise.

    Since [tex]F_c=m\omega^2R[/tex]

    [tex]F_a=m_a\omega^2R_a[/tex] and [tex]F_b=m_b\omega^2R_b[/tex]

    The ratios I obtained were: [tex]m_b=\frac{m_a}{2}[/tex] and [tex]R_b=\frac{R_a}{2}[/tex].

    When I find the ratio, I get:
    [tex]\frac{F_a}{F_b}=\frac{m_a\omega^2R_a}{m_b\omega^2R_b}=\frac{m_aR_a}{\frac{m_a}{2}\frac{R_a}{2}}[/tex]

    My end result will be the value, 4, which is not 1, which I am looking for in order for the forces to be equal.

    Is there a problem with my method, or is the answer given the wrong answer?
     
  2. jcsd
  3. Oct 18, 2005 #2

    Doc Al

    User Avatar

    Staff: Mentor

    I agree with your analysis. The answer is wrong. (Or someone messed up the problem statement.)
     
  4. Oct 18, 2005 #3
    Thank you.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Circular Motion - Quick Help Please!
Loading...