KNEX Education Simple Machines Deluxe GEARS, Руководство для учителей

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Every gear has a job to do
When a garden hose is turned on full power the water comes spraying out fast. If you connect the
hose to a sprinkler, you can use the power of the water to make the sprinkler move.The fast-moving
water turns a small turbine inside the sprinkler, which rotates the worm.The worm turns the worm
gear, which is connected to parts that move the sprinkler arm slowly back and forth.
Journal Ch
eck
✓
Explanation of how a
worm and
worm gear function
✓
Illustration of the dir
ection worms
and worm gears turn
✓
Number of rotations
of the Worm
Gear in one minute
✓
Number of teeth on
the Worm Gear
✓
Number of turns of t
he Worm to
that of the Worm Ge
ar
The Worm and Worm Gear Lesson Plan
Materials
-stopwatch or clock
with second hand
Objectives
• Identify a worm and worm gear
• Demonstrate how a worm and worm gear function
• Explain the advantages offered by worm gears and their
effect on force and speed
• Determine if worm gears change force, speed or direction
• Practice basic math skills
• Compare and contrast worm gears with other gears
Lesson Length:
30-45 minutes