http://www.ck12.org Chapter 9. Rotational Motion
Now, in order to find the tension in the cable, we’ll sum the torques on the rod with the hinge as the axis of rotation.
Notice that the sign of the torque due to tension in the cable and the torque due to the rod’s weight will be opposite
signs because they would cause the rod to rotate in opposite directions.
Στ= 0
mg
r
2
−Tsin(θ)r= 0
T=
mgr
2 sin(θ)r
T=
mg
2 sin(θ)
T=
2 kg∗ 9 .8 m/s^2
2 sin( 45 )
T= 13 .85 N
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