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What are
Spur Gears?
Spur gears are sets of gears that work together by
being set in the same position. The teeth on the edge
of one gear mesh with the teeth on the other gear.
When you turn one gear, the other gear turns in the
opposite direction.
Spur gears can be the same size or different sizes. If the
sizes are different, the gears will turn at different speeds
and with different amounts of force.
Here’s an example.
Spur gears inside a wristwatch make the hands
turn. When you wind the watch, you wind up a
spring that powers the gears. Small and large
spur gears work together to make the hands
turn at different rates, so you can tell the time.
How do spur gears help you?
Spur gears of different sizes can help you by
making parts of a machine turn at different
rates. When a small gear and a large gear work
together, the small gear turns faster than the
large gear. Its circumference is smaller, so it
doesn’t have as far to go to make one
complete turn.
In a wristwatch, small and large gears work
together to make the second hand turn a full
circle within a minute; the minute hand turn a
full circle within an hour and the hour hand
turn a full circle within twelve hours.
Different-sized spur gears also turn with dif-
ferent amounts of force.These gears can help
you when you use a machine that requires
extra force to do a job.
STUDENT REFERENCE SHEET
Содержание Education Simple Machines Deluxe GEARS
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