According to the principle of inertia, what will objects in motion do?

• A. Change direction
• B. Stay at rest
• C. Stay in motion along the path they travel
• D. Accelerate indefinitely

Answer: (C)

The principle of inertia is derived from Newton's First Law of Motion, which states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force. This means that an object that is already in motion will continue to move in the same direction and at the same speed unless a force causes it to change that state. Hence, when considering what happens to objects in motion, the correct understanding is that they will continue to move along the path they are currently traveling unless disrupted by an outside influence, such as friction, gravity, or a collision. This principle is fundamental in understanding how motion works and the importance of forces in altering that motion.