Moment of Torque; Am I solving this correctly?

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    Moment Torque
AI Thread Summary
The discussion revolves around calculating the torque produced by two 30N forces acting on a 90cm metal rod with a disc at its center. The torque of the couple is calculated as 2700 Nm, which is derived from the distance between the forces and their magnitude. To prevent rotation, the tension in the rope attached to the disc must equal the torque produced, leading to a calculated tension of 112.5 N. Participants emphasize the importance of including units in calculations for clarity. The calculations presented are confirmed as correct, providing reassurance to the original poster.
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Homework Statement


A metal rod of length 90cm has a disc of radius 24cm fixed rigidly at its centre(refer to picture attached). The assembly is pivoted at it's centre.
Two forces, each of magnitude 30N, are applied normal to the rod at each end so as to produce a turning effect on rod. A rope is attached to the edge of the disc to prevent rotation
1-Calculate the torque of couple produced by the 30N forces
2-the tension T in the rope
ametalrod.png

Homework Equations


Torque= moment arm * force applied perpendicular to pivot
torque of couple=distance between two forces * one of the force
(I assume the above equations will be relevant)

The Attempt at a Solution


For the rod the torque of couple would be
30 * 90 =2700

Now since the rotation is to be prevented by the disc in center it has to produce an equal torque in the opposite direction(anti-clockwise direction) so the torque produced by disc should also be 2700
and since
torque=moment arm*force applied
=radius*tension in string
2700= 24 * T
T=2700/24Have I solved the above numerical correctly? Since the book doesn't provide answer to these questions and I have no tutor I have no other way to confirm my calculations.
 
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That looks real good. Well done.
 
That's all fine, except that you really should state the units everywhere.
 
Thanks, everybody. That's a relief.
Secondly, I'll make sure to mention the units from here on.
 
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