A condition for mechanical equilibrium is that the sum of the forces acting equal zero. Another condition is that the sum of the _____A) centrifugal forces also equal zero B) centers of gravity balance.C) torques equal zero.D) rotational inertias equal zero.

Question

E) centripetal forces also equal zero.

Answer 1

The condition for mechanical equilibrium is that the sum of the forces acting on an object must equal zero. This means that all forces in all directions must balance out. So, option A) centrifugal forces equal zero is incorrect because centrifugal forces are not part of the external forces acting on the object. Option B) centers of gravity balance is also incorrect because the concept of balancing centers of gravity is not related to mechanical equilibrium. Option C) torques equal zero is the correct answer. Torque is the rotational equivalent of force, and in order for an object to be in equilibrium, the sum of the torques acting on it must be zero. Option D) rotational inertias equal zero is incorrect because rotational inertia is a physical property of an object and does not affect the equilibrium condition. Option E) centripetal forces equal zero is incorrect because centripetal forces are not external forces acting on the object, but rather the force required to keep an object moving in a curved path.