DYNAMICS The study of why objects move or dont move.
What is the natural state of motion of an object?
Aristotle Observed: All objects eventually come to a stop. Therefore he concluded the natural state of motion for an object, is for the object to be at rest. He Incorrectly concluded that the only way an object stays in motion is if it has a force acting on it. But, what is a force?
Force – A push or a pull caused by the interaction of two objects. F = Force Units: Newtons (N) or pounds (lb) 1lb = 4.45N A force is a vector quantity – It has magnitude (value) and direction.
Weight is a Force It is caused by the interaction between the earth and an object. It has a value and a direction (down). Objects have the same mass everywhere, they only have weight when they interact with a planet, like earth. A 150lb person has a weight of 668N.
Copernicus Observed: The motion of the stars and planets. He concluded that the earth was in constant motion. This idea was highly controversial. People preferred to think the earth was the center of the universe. As a result he was persecuted and had to work in secret.
Galileo devised experiments to discover the natural state of motion. His experiments represent the birth of modern day science. He also suffered persecution for his efforts.
Sir Isaac Newton was the next major player on the scene He was born on Christmas day, the year Galileo died. His work influenced todays world at a monumental level. He developed three laws that describe the motion of everything. He very well may have been one of the most influential human beings to ever live. And you thought he was just some dumb guy who got hit on the head with an apple.