1. Newton’s First Law – Law of Inertia:
– Objects at rest remain at rest, and objects in motion continue in uniform motion unless acted upon by an external force. This principle is known as Newton’s first law of motion.

2. State of Rest or Motion:
– An object at rest will not experience any displacement in the absence of an external force. It remains stationary due to its inherent property called inertia.
– If an object is already in motion without any external force acting on it, it will continue moving at a constant velocity in a straight line without experiencing any change in displacement.

3. Role of Inertia:
– Inertia is the tendency of an object to resist changes in its state of motion. It allows objects to maintain their current state unless influenced by an external force.
– In the absence of forces, inertia enables an object to continue its state of rest or motion without any change in displacement.

4. Examples Illustrating Displacement Without External Force:
– A hockey puck sliding on an ice rink will continue gliding in the absence of friction or external forces, demonstrating displacement due to inertia once set in motion.
– Consider a satellite orbiting in space. In the vacuum of space with negligible resistance, the satellite follows its path without any external force, experiencing displacement due to inertia.

5. Natural Phenomena and Inertia:
– Celestial bodies such as planets and moons can move in space due to their inertia and the absence of significant external forces, showing displacement without an applied force.

6. Discussion Point:
– The concept challenges the common perception that every movement requires a force. It highlights the significance of inertia in governing an object’s behavior when no external forces act upon it.

Understanding these points based on Newton’s first law provides insights into the role of inertia in allowing displacement of objects in the absence of external forces, encouraging discussions on the fundamental nature of motion and forces.