Semester 2 Physics! (And Jokes.. but not really)

     Welcome to the new lessons, which will cause new frustrations.  It is important to review definitions and material from 8th grade physics, as the information can change, but an important base of knowledge on the information can help.  

Basic Definitions:

Momentum: a measure of an object's tendency to move in a straight line with constant speed. It is the product of mass and velocity. In as much as velocity is relative, momentum depends on the frame of reference used to observe events.  (Product of mass and velocity).

Force: a push or pull upon an object resulting from the object's interaction with another object. Whenever there is an interaction between two objects, there is a force upon each of the objects. When the interaction ceases, the two objects no longer experience the force. Forces only exist as a result of an interaction.

Net force:  amount of force that allows an object to change direction or its motion.  

Newtons 3 Laws of Motion

First law of motion:  an object at rest will remain at rest unless acted on by an unbalanced force.  An object in motion continues to stay in motion at a constant speed and direction unless acted upon by an unbalanced force.  "Law of inertia",

Second law of motion:  acceleration is produced when a force acts on a mass.  The greater the mass of the object accelerating,  the greater the force to accelerate the object. 

This gives us a relationship between mass, force, and acceleration.  F= MA or force equals mass times acceleration.  

Third law of motion:  for every action, there is an equal and opposite re- action.  

This means that for every force there is a reaction force that is equal in size, but opposite in direction. That is to say that whenever an object pushes another object it gets pushed back in the opposite direction equally hard.

Important Information

• These three laws state:If an object experiences no net force, its velocity will remain constant

• The acceleration of an object is parallel and directly proportional to the net force acting on the object, is in the direction of the net force and is inversely proportional to the mass of the object.When a first object exerts a force on a second object, the second object simultaneously exerts a force on the first object, meaning that the force of the first object and the force of the second object are equal in magnitude and opposite in direction.The first law of motion defines only the natural state of the motion of the body ( when the net force is zero)

• The second law of motion states that the net force on an object is equal to the rate of change of its linear momentum.  Linear momentum of an object is a vector quantity that has both magnitude and direction.

I will never get over these jokes.  Check my blog post from a long time ago to find out more!

Cool.