Forces+and+Newton's+Laws

Newton's Laws: 1. An object at rest will stay at rest, and an object in motion will remain in motion, unless it is acted upon by some external net force. Inertia - the tendency of an object not to accelerate ex. - a brick sliding across carpet, a brick sliding across ice , obviously the brick sliding across ice will travel further than the brick sliding across carpet in the absence of applied force 2. The acceleration of an object is directly proportional to net force and inversly proportional to the mass of the object. Net force - the vector sum of all forces acting upon an object, when there is no applied force upon an object the object is known to have a net force of zero, the difference between weight and mass is weight is how much an object weighs under force when mass is how much material an object is made up of. For example a 100 pound weight will not weigh 100 pounds on the moon, but the 100 pound weight has not changed, it's still the same 100 pound weight. Equation - Force = Mass x Acceleration 3. The magnitude of force between two objects is equal and opposite in direction, the force of object 1 on object 2 is equal and oppostie in direction than the force of object 2 on object 1. Normal force - a force that acts on a surface in a perpendicular direction to the surface (every action has an equal and opposite reaction) ex. a baseball player hits a ball, the bat has a applied force to the ball and the ball has an equal and opposite force on the bat, the bat hits the ball and the ball accelerates, Friction - an opposing force that is exerted on an object in contact with another surface,the dependence of frictional forces on a particular object is called the coefficient of friction, the resistive force that keeps an object from moving is static friction, the retarding froce that act upon a moving object is called kinetic friction, the two things friction is dependent on is normal force and gravity.