Friction

What is friction?Edit

Friction is a force, affects motion. Friction acts on materials in contact with another, or acts in different direction in opposite motion.

What does the force of friction depend on?Edit

  • Nature of the materials.
  • How hard the surfaces are pressed together

..such as Rubber vs. Concrete, and not Steel vs. Steel (Rubber vs. Concrete > Steel vs. Steel)

Static Friction :Edit

Friction between the surfaces in contact and which are relatively at rest.

  • Opposes movement of stationary object
  • Moving furniture
  • Hardest part getting moving
Kinetic FrictionEdit
  • Acts on objects in motion
  • Once object begins moving, less force to keep in motion
  • Sliding, Rolling, Fluid
Sliding FrictionEdit
 
Basketball shoes prevent slipping, relation to Sliding Friction
  • Two objects slide past one another
  • Basketball shoes prevent slipping
Rolling FrictionEdit
  • Objects such as wheel or ball rolls across surface
  • Easier to overcome than sliding friction
  • Rolling friction is always less than static friction, as the time period for contact of irregularities between the bodies is less in rolling friction compared to static friction.
Fluid FrictionEdit
 
Boy with a helmet, on training wheels, relation to Fluid Friction
  • Solid objects move through fluids
  • Cyclists use aerodynamic and spandex to reduce friction
  • Vehicles such as aeroplanes and cars have a special shape known as streamlined shape to reduce windshear or drag.
Air ResistanceEdit
  • Friction acting on something moving through air
  • Don't notice unless at high speed.