Contents --- Newton's Law of Gravity
Introduction
Newton's Laws of Motion
Newton's 1st law: inertia
Newton's 2nd law: F = m×a
Newton's 3rd law: action = -reaction
Review Questions
Universal Law of Gravity
Characteristics of Gravity
---why it is the most important force in astronomy.
Review Questions
Mass vs. Weight
Review Questions
Inverse Square Law
Review Questions
Gravitational Acceleration
Measuring the Mass of the Earth
Review Questions
A Closer Look at Newton's Gravity
Occam's Razor and the Progress of Motion Laws
Nature of Gravity
Machine Universe
Material World
Review Questions
Orbits
Centripetal Force
Measuring Planet and Star Masses
Orbital Speed
Escape Velocity
Review Questions
Kepler's Third Law
Interplanetary Trips
Review Questions
Tides
Tides Slow Earth Rotation
Tides Enlarge Moon Orbit
Tidal Effects Elsewhere
Review Questions
Astronomy Notes home