Final answer:
A rotating body is in equilibrium when it has zero net torque and rotates with a constant angular velocity, indicating no angular acceleration.
Step-by-step explanation:
A rotating body can be in equilibrium if certain conditions are met. This generally means that the body is experiencing zero net torque and is rotating with a constant angular velocity, implying no angular acceleration. To give an example, consider a merry-go-round at a playground that is turning at a constant speed; it's in rotational equilibrium because its angular velocity is constant, and no additional torques are causing it to accelerate or decelerate.
An object such as a spinning top exhibits rotational equilibrium when it spins smoothly without wobbling, which indicates that there is no unbalanced torque acting on it. As a result, the state of equilibrium can be summarized as:
Zero net torque acting on the body (b).
Constant angular velocity (a), indicating no angular acceleration.
Constant moment of inertia (c).
Together, these conditions ensure that the object in question stays in a consistent state of rotation without any changes in its motion, hence being in equilibrium.