How Does Using ##m## Instead of ##M = 2m## Affect the Seesaw and Spring System?

AI Thread Summary
The discussion centers on calculating the torque about the pivot point S in a seesaw and spring system. The user initially calculates the torque from the plate's weight and the spring force but overlooks the impact of using ##m## instead of the correct mass ##M = 2m## for the disk. It is clarified that the weight of the rod does not contribute to torque since it acts directly on the pivot. The confusion arises from the incorrect mass assumption, which affects the overall torque calculation. Accurate mass representation is crucial for determining the system's behavior.
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Homework Statement
seesaw
Relevant Equations
torque
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The question ask to find torque about the pivot point S.
I first find the torque due to gravity of the plate and then torque due to spring force.
I understand that the weight of the rod do no torque as it is acting on the pivot S.
Where have I gone wrong?
 
You used ##m## instead of ##M = 2m## for the mass of the disk.
 
Orodruin said:
You used ##m## instead of ##M = 2m## for the mass of the disk.
thank you so much
 
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