PCS 125 Lecture Notes - Lecture 1: Inverse-Square Law, Unit Vector, Test Particle
Document Summary
Every particle in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the distance between them. G is the universal gravitational constant and equals 6. 673 10-11 n m2 / kg2. This is an example of an inverse square law. The magnitude of the force varies as the inverse square of the separation of the particles. The law can also be expressed in vector form. Where f12 is the force of particle 1 on 2 and the negative sign indicates that the direction of this force is opposite to the direction of the unit vector directed from particle 1 to particle 2. The negative sign also indicates that particle 2 is attracted toward particle 1. The forces form a newton"s third law action-reaction pair. Gravitation is a field force that always exists between two particles, regardless of the medium between them.
