Expert: Bobby Soltani - 12/5/2005

Question
How do you go about answering this question? "Prove that the centre of mass of a uniform wire in the form of a semi-circle of radius r is at a distance 2r/pi from the centre." Thanks for your time, Adam.  

Answer
Hi Adam,

The proof to this involves calculus.  Since it is hard for me to express integrals in this text only format, I found a website that works your same problem.  It uses a radius of 2, rather than r, so substute r^2 for 2^2 = 4.

http://www.math.ucla.edu/~ronmiech/Calculus_Problems/32B/chap14/section2/906d29/...

Let me know if you still have any questions.  Good Luck.

Bobby