# What is friction and what are the different types?

WHAT IS FRICTION AND WHAT ARE THE DIFFERENT TYPES
Friction is a force that acts between objects that are in contact with each other. Friction slows down or stops the movement between the two surfaces that are touching. The easier way of saying it is that friction opposes motion. Do you ever wonder what the kinds of Friction are? Well here they are ,the kinds of frictions that there are is dry friction, static friction, kinetic friction, air friction, fluid friction, lubricated friction, skin friction, and internal friction.

Figure 1: A picture If you look in a magnifying glass at a thing that you thing is smooth it is actually rough when you look carefully at it.

Figure 2: Friction is opposing motion to stop the box on the ramp.

More Than One Force
There are more types of forces than Friction. They are gravitational and magnetism forces. Gravitational is a pull because the gravity pulls you to the center of the earth but the floor pushes you up. Magnetism is a pull because the magnets poles of north and south with two magnets pull each other together. Sometimes Magnetism is a push because if two magnets that are faced by the same pole the magnets push away from each other. Now that you know that there is more than friction as a force.

Glossary
Forces-are any push or pull
Gravity- is a force pulling together all matter (pulls down to center of earth but floor pushes)
Magnets- is an object that makes a magnetic field

Citations
EHecht, Eugene. Physics. Pacific Grove: Brooks/Cole Publishing Company,1994. Print.

"Friction." Britannica Elementary Encyclopedia. Encyclopædia Britannica Online School Edition.

Encyclopædia Britannica, Inc., 2012. Web. 28 Sept. 2012.

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Kahan, Peter. Science Explorer Motion, Forces, and Energy. Needham: Prentice Hall, 2000. Print.

ST. Mary's H.S. Physics http://www.stmary.ws/highschool/physics/home/notes/dynamics/friction/introFriction.htm Mangiacapre, Tony. 1995. Web. 27 Sep, 2012

Wikipedia http://en.wikipedia.org/wiki/Magnet Wikipedia. 23 Sep, 2012. Web. 27 September 2012