Friction
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What is friction?
[edit | edit source]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 | edit source]- 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 | edit source]Friction between the surfaces in contact and which are relatively at rest.
- Opposes movement of stationary object
- Moving furniture
- Hardest part getting moving
Kinetic Friction
[edit | edit source]- Acts on objects in motion
- Once object begins moving, less force to keep in motion
- Sliding, Rolling, Fluid
Sliding Friction
[edit | edit source]- Two objects slide past one another
- Basketball shoes prevent slipping
Rolling Friction
[edit | edit source]- 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 Friction
[edit | edit source]- 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 Resistance
[edit | edit source]- Friction acting on something moving through air
- Don't notice unless at high speed.
quiz
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