1. The problem statement, all variables and given/known data Four particles are in a 2-D plane with masses, x- and y- positions, and x- and y- velocities as given in the table below: M X Y Vx Vy 1 8.9kg -2.6m -4.8m 3.2m/s -3.9m/s 2 7.9kg -3.4m 3.6m -5m/s -5.2m/s 3 9kg 4.7m -5.4m -6.3m/s 2m/s 4 8kg 5.5m 2.7m 4.1m/s - 3.3m/s OK, so it first asks: What is the x position of the center of mass and What is the y position of the center of mass I have answered these correctly as: CMx =1.07 CMy =-1.22 The next question asks: What is the speed of the center of mass:? I THOUGHT this would simply be sqrt[(CMx^2) + (CMy^2)] <-(the magnitude of CMy) which would be 1.622 m/s but this is INCORRECT. I have stared and re-read this question for an hour and simply cannot think of any other way to calculate. any thoughts would be greatly appreciated?