Torque and equilibrium; concept problem

AI Thread Summary
In the discussion on torque and equilibrium, participants clarify that net force and net torque are distinct concepts essential for understanding equilibrium. It is emphasized that net force is the sum of individual forces acting on a body, which can be zero even when forces create net torque. An example illustrates that opposing forces can produce zero net force while still generating torque. The conversation leads to a consensus that both net force and net torque must be considered for a body to be in equilibrium. Ultimately, understanding these principles is crucial for solving related physics problems.
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Homework Statement



I'm just trying to understand why the force from net torque isn't included in net force when considering equilibrium: Why isn't the force from torque part of the net forces acting on a body?

Homework Equations


if net force = 0 and net torque = 0 then the body is in equilibrium;
net force = ma, torque = Frsin@, where @ is theta


The Attempt at a Solution


It seems like the force required for torque should be part of the net forces acting on the body.
 
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"Net force" is not a force, it's the sum of individual forces. You can certainly have forces acting on something so as to create a net torque, yet those same forces add up to zero net force. For example: a vertical force to the right of center and an equal but opposite vertical force to the left of center.

And you can also have a net force on a body with zero net torque.
 
Doc Al said:
"Net force" is not a force, it's the sum of individual forces.

Agreed.

Your example helped me:
You can certainly have forces acting on something so as to create a net torque, yet those same forces add up to zero net force. For example: a vertical force to the right of center and an equal but opposite vertical force to the left of center.

Thanks.

So from this I now believe that the force from the torque actually is considered in the net force acting on the object. Now I am starting to understand why both net force and net torque need to be included for equilibrium.
 
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