1. The problem statement, all variables and given/known data Locate the x coordinate of the center of mass of the homogeneous rod bent into the shape of a circular arc. Take r = 170 . The arc goes from (-5/6) to (5/6)pi (counterclockwise). It has a radius of 170mm. 2. Relevant equations x=rcosθ, y=rsinθ, dL=r*dθ 3. The attempt at a solution I found "M" by integrating "170 dθ" from (-5/6)pi to (5/6)pi. This gave me 890.12mm. I found "My" by integrating "170 (cosθ) 170 dθ" from (-5/6)pi to (5/6)pi. This gave me 170^2 or 28900mm. I used My/M to find the x coordinate of the center of mass as 28900/890.12 or 32.468mm. However this is incorrect.