If the sum of all the forces acting on a body is zero, is it necessarily in equilibrium? If the sum of all the forces on a particle is zero1 is it necessarily in equilibrium?
No, in case of a body it is not necessary to be in equilibrium. As, we can see in the diagram there exists torque in the system though the force is zero. Hence there exists all the rotational parameters.
In case of a particle it remains in equilibrium when the resultant force is zero.
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