Simple Machines

1. A simple machine is any of the basic mechanical devices for applying a force, such as an inclined plane, wedge, or lever.
2. The six types are:
Pulley- flagpoles, sailboats, cranes
Lever- see-saws, car jacks, nutcrackers
Wedge- knife, doorstops, ax
Wheel and Axle- tires, doorknobs, steering wheels
Inclined Plane- boat ramp, stairs, wheelchair ramp
Screw- bolts, jar lids, drill bits
3.Levers- first, second, and third class.
4. Compound simple machines put more than one together and are designed to make work easier. You can combine them in ways such as creating a can opener or bicycle, something that not a single simple machine could do. Most machines are compound simple machines.
Sources:
www.jc-schools.net/write/compositions/machines.htm http://library.thinkquest.org/CR0210120/Compound%20machine.html www.mikids.com/Smachines.htm www.education.com › ... › Science Teacher Resources
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Car Crashes - Is Newton Part of the Equation?

Two cars are cruising down the highway, both set on their destinations and more than likely edging their way above the stabalized speed limit. Car A's driver, Toyota truck and all, might have had a triple shot of caffeine added to their coffee this morning, the only way to make it through the two hour trip without stopping. Car B, a convenient Honda, on the otherhand, might be a parent and their drooling, disgusting child on their way to visit grandma for the holiday weekend. Nothing can stop a family with the desire to reach the cookies when they're still fresh out of the oven. As they speed on, the force due to mass and acceleration begins to increase. According to Newton, the superior force can cause the other car to contort or react under the pressure of it's power. Think of this: a cocky teenage boy slams into a more underweight individual and knocks him to the floor. This same over-confident teenage boy tries to slam into the 250 lb quarterback... and he knocks himself off balance when his force isn't enough to move this large mass of a man. Car A is zipping at 72 mph, and Car B is cruising at 65 mph. Suddenly, without warning, coffee fanatic loses his buzz and drifts into the other lane, hitting the anticipated family of two head on. Both cars manage to convulse under the instantaneous force that is applied from opposite directions. Car B, however, it rocketed backwards backwards from the signifigantly larger force. Given that these two cars had an equal amount of force, they would have been stuck dead in their speeding tracks. Movement only happens when a larger force is exerter. However, is Newton really relevant in the circumstances that they're both doing their duty of road responsibility? That, on the otherhand, is a bigger problem.