Question

which statement describes dynamic equilibrium?
a. the forces on an object are unbalanced.
b. the forces on a stationary object are balanced.
c. an object is accelerating due to forces acting on it.
d. the forces on an object in motion are balanced.

Explanation:

Dynamic equilibrium occurs when an object is in motion and the forces acting on it are balanced. When forces are balanced, there is no net force, so the object moves at a constant velocity (Newton's first law). Option A: Unbalanced forces cause acceleration, not equilibrium. Option B: Stationary object with balanced forces is static equilibrium. Option C: Acceleration implies unbalanced forces (Newton's second law, \(F = ma\)). Option D: Object in motion with balanced forces fits dynamic equilibrium.

Answer:

D. The forces on an object in motion are balanced.