Circular Motion: Centripetal Force Comparison Between Andy and Bella

AI Thread Summary
Andy and Bella both move in circular paths with the same angular velocity, but their masses and distances from the center differ. Bella's mass is half of Andy's, and she is located at half the distance from the center compared to Andy. The centripetal force for each is calculated using the formula F_c = mω²R. The analysis shows that the ratio of their forces results in a value of 4, indicating that Andy experiences four times the centripetal force of Bella. Therefore, the initial assertion that they experience the same force is incorrect.
dekoi
Andy and Bella move in circular paths about a common point with the same constant angular velocity \omega. 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, F_c?

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

Since F_c=m\omega^2R

F_a=m_a\omega^2R_a and F_b=m_b\omega^2R_b

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

When I find the ratio, I get:
\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}}

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?
 
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I agree with your analysis. The answer is wrong. (Or someone messed up the problem statement.)
 
Thank you.
 
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