my attention span | 2004-12-12 13:36:57 ET |
Megan ******
3rd block
12-11-04
Everyday Physics of Brakes
Car brakes, and bicycle brakes use friction to work. It’s the same with most brakes. When your riding a sled and you press your foot against the ground, what happens? You slow down right? Well that’s because your foot is acting as a brake, and is using friction to slow you down. Another example is when you were little and you rode the little red wagon down a hill. When you got scared you would put your feet out in an attempt to stop before you hit something. Have you ever accidentally slid down the stairs and as soon as you began to feel yourself falling you put out your hands and pressed against the walls? Doing this is another example of using friction to stop.
Gravity also works as a brake on objects. When you are riding on a flat surface in your car and you release the acceleration pedal, what happens? Do you keep going at the same speed, or do you slow down? Gravity takes affect and the car slows down.
Gravity is nature’s friction. It’s the reason a ball stops after it has rolled for a distance. It’s the reason why baseball players don’t slide all the way around the world. Unfortunately its also the reason why water runs down my driveway and used to flood my garage….
See how I get off topic so easily?
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