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How to find location of the center of mass if 4 masses on a square?

Four Masses are arranged in a square one meter on a side as follows: (clockwise from the upper left hand corner) 8 kg , 1.2 kg , 10 kg , 3 kg . Assume that the 3 kg mass at the lower left hand corner is at x=0 and y=0. What is the x location, to the nearest cm, of the center of mass?

Public Comments

1. When a group of masses, M1, M2, ... are located at (X1,Y1) , (X2,Y2) , ... The CM coordinates (X,Y) are; X = (1/M)[M1X1 + M2X2 + ...} Y = (1/M)[M1Y1 + M2Y2 + ...] where M = (M1 + M2 + ...) ,total mass. Apply this to your square; X = (1/22.2)[8(0) + 1.2(1) + 10(1) + 3(0)] = 11.2/22.2 = .505 m = 51 cm Y = (1/22.2)[8(1) + 1.2(1) + 10(0) + 3(0)] = 9.2/22.2 = .414 m = 41 cm EDIT__________________________________ Debbie is correct. Standard round off procedure for 50.45 cm , to the nearest cm would be 50 cm.
2. Xcm = (m1*x1 +m2*x2+m3*x3 +m4*x4)/(m1+m2+m3+m4) So xcm = 8*0 + 1.2*1+10*1+3*0/(8+1.2+10+3) = 0.5045m = 50cm