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How do gears help you?
Gears can help you in three different ways.
Force
Gears can change the force you need to make
something move. When you turn a small gear, it
can make a big gear move.You have to turn it lots
of times to make the big gear turn around once,
but the small gear doesn’t take much force to
turn.
Speed
Gears can change the speed that a machine
moves. If two gears are different sizes, the smaller
gear will turn faster than
the larger gear.
Many machines use gears
of different sizes to make
certain parts of the
machine turn faster or
slower than others.
Direction
Gears can also change the
direction something
moves.When two gears
are linked together, they turn in opposite direc-
tions and can make parts of machines turn in op-
posite directions too. Gears can also be set up
where one gear is lying flat, but it makes an up-
right gear turn. Different arrangements of gears
make it possible for machines to do work in
many different directions.
Getting Starte
d
With Gears
What is a gear?
• A gear is a wheel with teeth along its outer edge.
• One gear can make another gear turn when the teeth of the
two gears interlock, mesh or connect.
• Gears can make work easier by letting you use less force to do a job.
• Some gears let you move a gear in one direction by turning another gear in a different direction.
• Other gears help by changing the speed of the turning parts.
Here’s an example of how gears
can help.
Imagine you work for a zoo.Your job is to build a
feeder to adjust the meals for an elephant named
Moe. Moe eats whatever food is put out for him so
his intake must be watched closely or he’ll overeat.
The zoo manager asked you to find a machine to
feed Moe specific amounts at the proper times. Im-
possible? NO! Not with the help of gears.
Picture this.
You could design a
huge plate which
rotates in a
circle. Along
the outside
of the plate are
large bowls with elephant-sized helpings for Moe’s
meals.Your design puts only one bowl in Moe’s
reach at a time. The speed the plate turns is con-
trolled by a series of gears underneath the plate.
This allows it to run at the right speed so Moe gets
fed at the proper time without your help.
A Bright Idea!
Gears were a pretty modern invention. Conduct
research to find out about the earliest use of this
simple machine.
STUDENT REFERENCE SHEET
Содержание Education Simple Machines Deluxe GEARS
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