Question

when an object has its motion changed, the cause is generally a. an external force b. an internal force c. an existential force d. an interval force please select the best answer from the choices provided.

Explanation:

According to Newton's first - law of motion, a body will maintain its state of rest or uniform motion in a straight line unless acted upon by an external force. So, a change in an object's motion is generally caused by an external force. Internal forces act within the object and do not cause a net change in its motion. "Existential force" and "interval force" are not terms related to the cause of motion change in physics.

Answer:

A. an external force