Motion and Rest

Sir Isaac Newton was one of the greatest scientists of modern times. Born in England, he made groundbreaking contributions to physics and mathematics. His most famous work, Principia, introduced the laws of motion, equations of motion, and the theory of gravity.

• Before Newton, Johannes Kepler had formulated three laws describing planetary motion, but the reason behind these motions remained unknown. Newton’s theory of gravity provided a mathematical explanation for Kepler’s laws, revolutionising our understanding of celestial mechanics.
• Beyond gravity, Newton made significant contributions to various fields, including light, heat, sound, and mathematics. He invented calculus, a powerful branch of mathematics with extensive applications in science. Additionally, he was the first to construct a reflecting telescope, improving astronomical observations.

Sir Isaac Newton

(1642-1727)

When an object changes its position continuously, we say the object is in motion. In other words, motion means "moving" from one place to another. Rest is when an object does not change its position with time. It stays in the same place.

1. Observation of Motion: When you are standing still, like at a bus stop, other things (like cars or bikes) seem to move. But when you are moving, like in a car or a train, still objects like trees or buildings seem to move backward. An object can be in motion when it is moving and changing its place. An object is at rest when it is not moving and stays in the same place.
2. Displacement: The change in the position of an object from one place to another is called displacement. For example, if a ball rolls from point A to point B, the distance between these two points is the displacement. An object in motion will always be changing its position, meaning it undergoes displacement. The continuous displacement of an object is called motion.