* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Newton`s 1st Law of Motion
Survey
Document related concepts
N-body problem wikipedia , lookup
Brownian motion wikipedia , lookup
Rigid body dynamics wikipedia , lookup
Hunting oscillation wikipedia , lookup
Mass versus weight wikipedia , lookup
Classical mechanics wikipedia , lookup
Modified Newtonian dynamics wikipedia , lookup
Centripetal force wikipedia , lookup
Classical central-force problem wikipedia , lookup
Newton's theorem of revolving orbits wikipedia , lookup
Seismometer wikipedia , lookup
Transcript
Newton’s First Law of Motion • Krishna Gopal Shrivestava of India set an unofficial world record in 1999 by pulling a ship with a mass of 244,000 kg with his teeth. We can use this feat to learn about force, mass, and acceleration. 1. How would a small rowboat be different if Shrivestava pulled it rather than a large ship? 2. In what direction did the ship move? Why do you think so? 3. When Shrivestava stopped pulling, did the ship stop moving? Explain. Famous Scientists The Laws of Motion Great ideas on motion! Section 1: The First Law of Motion Objectives: • Define Newton’s first law of motion. • Explain how inertia and mass are related. Aristotle (300 B.C.) Greece • His ideas were popular for ~2,000 years. • Now, his ideas are obsolete. • 2,000 years of false knowledge WRONG!! What Aristotle said: • Heavier objects fall faster than lighter ones • Earth is the center of the universe • All motion on Earth is straight and linear Aristotle (300 B.C.) Greece (cont.) Aristotle’s ideas about motion were a beginning in scientific thought. Galileo Galilei (1600’s) Italy • Discovered moons of Jupiter • Supported the idea that planets revolve around the Sun • Famous for ideas on motion…but these were not readily accepted in his time Galileo Galilei (cont.) Galileo’s Ideas on Motion: 1. All objects fall at same speed (independent of weight) 2. Introduced concept of friction- which slows things down 3. Inertia (sluggish or lazy)- tendency of an object to resist a change in its motion Sir Isaac Newton (1700’s) England • “Father of Physics” – Devised calculus – Explained gravity, the universal law of gravitation (apple on head?) – Formulated a theory on the nature of light – Formulated the laws of motion Newton’s 1st Law of Motion • An object at rest remains at rest… • An object in motion maintains its velocity… • Net force = 0 – balanced forces, no acceleration! Unless it experiences an unbalanced force First Law (cont.): INERTIA • Newton borrowed the idea from Galileo. • The inertia of an object is the tendency of the object to resist a change in motion. • The larger the mass of an object, the greater its inertia. Newton’s 1st Law of Motion Apply Newton’s 1st Law of motion to this picture: Newton’s 1st Law of Motion Sports Examples: • A moving ball will keep moving forever. Unless slowed by external force of friction (ground, floor) or gravity • A soccer ball in grass remains stationary. Until it is kicked (external unbalanced force)