Newton's+Laws


 * __Newton's Laws__**

Inertia- is the resistance of an object to a change in its state of motion. One example is when you are driving a car and you have a drink. When you accelerate and brake your drink remains where it is. The drink stays where it is because the road provides an unbalanced force on the spinning tires, to keep the drink where it is. Another example is your standing somewhere minding your own business and you are facing north. Some bully comes up behind you and tackles you in the back. Your body goes forward but your head flys back. Your head flys back because it wants to stay stationary.
 * 1st Law**- An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Net Force- is a vector produced when two or more forces act upon a single object. A net force can also be defined as the overall force acting on an object, when all the individual forces acting on the object are added together. Weight Vs Mass on the moon- Weight is the measurement of the pull of gravity on an object. Mass is the amount of matter an object has. On the moon there is less gravity so a person will have more mass then weight on the moon. Mass never changes because it does not have anything to do with gravity. a = Fnet / m Fnet = m * a
 * 2nd Law**- Acceleration of an object is dependent on two variables; net force acting upon the object and the mass of the object.

The normal force is the support force exerted upon an object which is in contact with another stable object. For example, if a book is resting upon a surface, then the surface is exerting an upward force upon the book in order to support the weight of the book. On occasions, a normal force is exerted horizontally between two objects which are in contact with each other. For instance, if a person leans against a wall, the wall pushes horizontally on the person. An action reaction pair has a pair of forces working acting on the two interacting objects. Friction is a force which causes the motion between two surfaces to be reduced. Coefficient of Friction- The magnitude of the force between two objects in contact to the magnitude of the normal force with which the objects press agaisnt eachother. Kinetic Friction- the force that opposes the movement of two surfaces that are in contact are sliding over each other. Static Friction- the force that resists the initiation of sliding motion between two surfaces that are in contact and at rest. Friction depends on the pair of surfaces.
 * 3rd Law**- For every action, there is an equal and opposite reaction. W henever objects A and B interact with each other, they exert forces upon each other.