Final answer:
An object will maintain its state of motion unless acted upon by an external force. Friction and centripetal force are examples of external forces that can cause a change in an object's motion, in line with Newton's laws of motion.
Step-by-step explanation:
An object will move at the same velocity UNLESS an external force acts on it. This concept is a key point in understanding Newton's First Law of Motion, often referred to as the law of inertia. In the absence of an external force, an object at rest will remain at rest, and an object in motion will continue to move at a constant velocity in a straight line.
Friction is an example of an external force that can affect an object's motion by opposing it. Another type of external force that can affect motion is centripetal force, which is necessary for an object to maintain uniform circular motion by causing constant acceleration due to a change in direction. According to Newton's second law, any acceleration requires a net external force.
Therefore, if there is no net external force acting on an object, such as when an object is in outer space away from significant gravitational influences or atmospheric friction, it will not experience any change in motion unless acted upon by one.