wind turbine kit,
blood type test,
Experiment with Gears
Simple Machines Science Projects
Gears can help us do work by speeding up or changing the direction
of motion. To see how this works, make a model set of gears!
What You Will Need:
What To Do:
You've just built a gear train. The big gear is the
driver. Try turning it slowly. What happens to the little gear?
Which way does it turn? Draw a big colorful dot on each gear, and
position the gears so that both dots are at the top. As you turn the
big gear, have one person count how many times the big gear turns
all the way around and another person count how many times the small
gear does. Do they turn the same number of times?
out the pattern for the gears and color them however you like.
You can cut them out if you want, or just tape the whole paper
to the Styrofoam tray.
- Have an adult cut the Styrofoam around the pattern to make
Styrofoam gears. (The easiest way to do this is to cut out a
circle along the outside edge of the teeth, then make the cuts
around the teeth.)
- Once you have your gears cut out, use thumbtacks to pin them
to a piece of cardboard or another tray. Pin them so that their
teeth fit together.
- If you want to, you can make a small turning handle on the
big gear by taping a little piece of Styrofoam so it stands
straight up on the gear.
Gears work to change the direction of motion. When you turned the
big gear one way, the little gear turned the other way! Gears also
change speed of motion. When you turn the big gear slowly, the
smaller gear turns faster. This helps save energy, because you don't
have to work as hard to turn the big one slowly as if you had to
turn the small one quickly.
You can also try this project with water bottle caps that have
ridges, or with gears from a building set like Lego or K'Nex.
See How a Screw Works
An inclined plane, such as a ramp, is a kind of simple machine that
helps do work. A screw, just like the ones from a hardware store, is
also a simple machine! A screw is made from an inclined plane being
wrapped around and around. To see how this works, you will need
notebook paper, and a pencil or marker.
Because of the inclined plane, screws can hold all sorts of things
together. If you like, try making different shapes and sizes of
triangles, and wrap them around a marker or pencil to make different
kinds of screws.
- Cut 2.5 inches off a piece of printer paper to make a
- Fold the top corner over until it meets the opposite bottom
corner - you've now made a triangle! The long edge looks like an
inclined plane, although the paper is too thin to do any real
- Starting from one of the short sides of the triangle, wrap
the paper once around the pencil or marker, then start rolling
until the whole piece of paper is wrapped around the maker.
- Put a finger on the end of paper to keep it from unrolling,
and carefully pick up the screw you have made. Do you see how
the long edge of the triangle is now traveling around and up the
marker? This is just like the inclined plane wrapped on a screw!