AST101H5 Chapter Notes - Chapter 4: Dn2, Net Force
Document Summary
Speed = change in position or location in some amount of time. Velocity = change in position or location + direction in some amount of time = m/s. Acceleration = change in velocity in some amount of time = (m/s)/s = m/s^2. Momentum has a direction because velocity does: changing velocity means changing momentum. Mass = sum of all the matter in an object(molecules and atoms) Weight = force of gravity attracting the mass of an object. Example: an astronauts mass is the same on earth as it is on the moon. 1st law: if there is no net force, an object"s momentum does not change. 2nd law: if there is a net force, the object"s momentum does change: equation: net force = mass * acceleration. F = ma (3rd law: forces come in opposite pairs. Every action has an equal and opposite reaction. ) Gravity is a univesral force between all objects that have mass.
