Concept explainers
Does a rigid object in uniform rotation about a fixed axis satisfy the first and second conditions for equilibrium? Why? Does it then follow that every particle in this object is in equilibrium? Explain.
Explanation of Solution
Equilibrium defines the state in which all the opposing actions are balanced.
The equilibrium conditions are- first condition is that the vector sum of forces must be zero and the second condition is the sum of torques about any point must be zero.
When a rigid body is uniformly rotated about a fixed axis, then the object does not possess linear motion or translational motion. Thus, it satisfies the first condition of equilibrium.
Since rotational motion is uniform then no torque acts on it. Thus, it satisfies the second condition for equilibrium. Every particle in the rigid object also is in equilibrium because the particles position remains constant and does not get affected by the rotational motion.
Conclusion:
The rigid object is in equilibrium as it satisfies both the condition and every particle of an object satisfies the equilibrium conditions.
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