We have a block of un-uniform density of mass m suspended by two massless wires, against gravity. The left wire makes an angle phi_1while the right angle makes an angle phi_2. The block has length L. They want me to find the center of mass.(adsbygoogle = window.adsbygoogle || []).push({});

THis is what ive done:

We have tension in the wires. Torque is force measured from a distance. In our case, the two wires create a torque about the center of mass. I find the forces,

F_1 = sin(phi_1)*m*g

F_2 = sin(phi_2)*m*g

And realize that the torques are

t_1 = F_1*x_c_m;

t_2 = F_2*(L - x_c_m)

since they equal another (net torque is zero), i set them t_1 = t_2 and solve for x. However the answer is incorrect and I am told to check my trignometry. My answer is

x = (L sin(phi_2)) / (sin(phi_1)+sin(phi_2))

whatever am i doing wrong?

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# Torque and center of mass question

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