- #1
Toranc3
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Homework Statement
A 0.9 kg mass at (x, y) = (20 cm,20 cm) and a 2.0 kg mass at (20 cm,100 cm) are connected by a massless, rigid rod. They rotate about the center of mass.
Homework Equations
x=(m1*x1+m2*x2)/(m1+m2)
y=(m1*y1+m2*y2)/(m1+m2)
I=1/12*ML^(2)
The Attempt at a Solution
What are the coordinates of the center of mass?
I got 0.20m and 0.752m
What is the moment of inertia about the center of mass?
I used this 1/12*(m1+m2)*(L1x+L2x+L1y*L2y)^(2)
1/12*(0.9kg+2.0kg)*(.552-.248)^(2)
I get 0.02233kg*m^(2) but this is wrong. The answer is 0.397kg*m^(2)
What am I doing wrong?