testreview


 * Newton's Law of Universal Gravitation**
 * Isaac Newton believed that gravitation forces were responsible for the acceleration o objects on the moon and earth.
 * Newton concluded that any two objects in the universe exert gravitational attraction on each other.
 * Universal Gravitation and mass:
 * As the mass of either object or both objects increases, the force of gravitational attraction increases.
 * Universal gravitation and distance:
 * As the distance separating two objects increases, the force of attraction is exponentially smaller.

forces can be attractive or repulsive. whether it is a proton or electron but is NOT part of the magnitute of the charge.
 * Friction**
 * Friction is often minimezed in solving force and motion problems, but in the real world friction is everywhere.
 * The static friction acts in response to other forces.
 * The kinetic friction force is the force exerted on one surface by the other when the forces are in relative motion.
 * The static friction force is the force that opposes the start of relative motion between the two surfaces in contact.
 * Coulomb's Law**
 * Shows relationship among electrical forces changes and distance. It is like Newtons Law of Gravity but unlike gravity electric
 * The charge (q) of a particle is NOT a vector quantity, therefore when describing as POSSITIVE or NEGATIVE that tells
 * Electric Fields**
 * A vector quantity that relates the force exected on a charge to the size of the charge.
 * The magnitute of the electric field is measured in N/C (Newtons/Coulomb's).
 * Electric Field Lines**
 * Direction of arrows indicates the charge of the field.
 * Away from a positively charged object.
 * Toward a negatively charged object.
 * Electrical Current**
 * Flow of charged particles
 * Current always flows from a higher potentional difference (voltage) to a lower potentional difference.
 * Grownding**
 * Touching a body to eaarth to eliminate excess charge.
 * Earth is so large it almost any charge can flow to it until electric potential difference is zero (equipotenial).