Hey. I totally forgot what the simple machines are. Theres the wedge, the screw, the lever…am I right? Are those complex machines? Is a funnel a simple machine?
Anyway…
Probably depends on your definition of a machine.
Aren’t there like four or five basic "simple machines"in science. I don’t mean like a clock, a contraption of moving parts, but the DNA of machines, if you will. Arent there four or five simple machines in science?
How about the roller or wheel ?
In addition to the three you mentioned, there’s also the wheel and axle, inclined plane, and pulley.
http://www.coe.uh.edu/archive/science/science_lessons/scienceles1/finalhome.htm
I forgot to say, a compound machine has two or more simple machines in it. Think of simple machines as atoms, and compound machines as molecules.
I always had a problem with the screw and the inclined plane being considered separate simple machines. A screw is just an inclined plane in a spiral.
Maybe that’s just my problem.
Let’s see: There’s the Mixer, the Blender, the Stirring Straw, the peanut vending machine, and the megatouch. All can be found at McSwiggans (New York’s best Irish Pub).
DaLovin’Dj
The piston can also be considered a simple machine: Two hydraulic pistons of different sizes, and connected by a hose or pipe, can do the same thing as a lever, even though the device includes none of the textbook “simple machines”. There’s also the matter that the wheel, in its most common form, does not change the amount of force exerted nor the distance over which it’s exerted; you need at least two wheels on the same axle, and some way to connect wheels (belts or gear teeth, or the like) to do that.
Personally, I suspect that the whole notion of “simple machines” is just something that’s swapped around among elementary school science books as cheap filler.
I’m with you. This morning’s “Ask Marilyn” column cited the same six as Lynn. My first thought was that there were really only three since a pully is the same basic device as a wheel/axle and the wedge, inclined plane, and screw are all variations on a theme.
Maybe this is mechanics for the new century in the same vein as citing Ohm’s three laws when teaching electronics to people who don’t know algebra…
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Ohm’s 3 laws?? As far as I know, he’s only got 1 law. Are you including Kierchoff’s voltage and current laws?
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When you teach electronics to people who’ve never studied algebra, it’s easier to teach Ohm’s Law as three:
- V = IR
- I = V/R
- R = V/I
If you don’t know algebra, #2 and 3 don’t necessarily follow from #1, but it’s easy to memorize all three so you can choose the one that solves for your variable of choice.
I know people who actually teach this, but it’s also the canonical example of expanding basic principles to make them easier to grasp. That’s why I brough it up in relation to the six simple machines.
Thanks for explaining. I guess I kinda whooshed on that one.