AS101 Chapter Notes - Chapter 3: Circular Motion, Semi-Major And Semi-Minor Axes, Geocentric Model
Document Summary
First principle something that seems obviously true and needs no further examination. Geocentric universe a model of the universe with earth at the centre. Describes other objects from earth"s point of view. Geocentric model is also known as ptolemaic system - explains how planets, the sun, and stars orbit around earth. Uniform circular motion combinations of circles turning at uniform rates. Parallax the apparent motion of an object because of the motion of the observer. Heliocentric universe a model of the universe with the sun at the centre. Paradigm a commonly accepted set of scientific ideas and assumptions. Ellipse a closed curve around two points, called the foci, such that the total distance from one focus to the curve and back to the other focus remains constant. Semi-major axis half of the longest diameter of an ellipse. Eccentricity a number between 1 and 0 that describes the shape of an ellipse (how elongated it is)
