ASTR 1000 Chapter 4.4-4.5: ASTR ch. 4.4 & 4.5
Document Summary
Universal law of gravitation fg= g (m1m2/d2) Chapter 4. 4 and 4. 5 attracts every other mass through a force called gravity. 1: strength of gravity is directly proportional to the product of their masses. Inverse square law strengthen of gravity between two objects decreases. 3. with the square of the distance between their centers. Bound orbits orbits in which an object goes around & around another: ellipses are the only possible shape for these orbits. Unbound orbits path that brings an object close to another just once. *two objects attracted by gravity orbit their common center of mass* 4. 5 orbits, tides & the acceleration of gravity. Orbital energy the sum of its kinetic energy & gravitational potential energy: stays the same no matter what. Gravitational encounter when two objects pass near enough to each other where they can feel each other"s gravity.