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Journal Ch
eck
✓
Identification of the t
ype of gears in the
Lawnmower
✓
Explanation of how t
he spur gears functio
n
✓
Calculations of gear r
atios
✓
Comparison of the d
ifferent gear
configurations and ra
tios
✓
Assessment of which
gear arrangements
would be most effect
ive and why
✓
Description of the sc
issor action of the
Lawnmower
The Lawnmower Lesson Plan
Materials
-green tissue paper
-scissors
-tape
-extra K’NEX pieces
Objectives
• Identify the type(s) of gear used in a lawnmower
• Demonstrate how a lawnmower functions
• Explain the advantages offered by spur gears and
their effect on force and speed
• Determine if the spur gears in the Lawnmower change force, speed
or direction
• Calculate and demonstrate the significance and advantage of
gear ratios
Every gear has a job to do
This type of lawnmower is not used much anymore but surprisingly, most kids are familiar with it.The gears in
a real push mower are not visible from the outside, which is typical of spur gears but they work in the same
way as the Gears in the K’NEX Lawnmower.The different speeds of the wheels and the rotating blades
give a clue that gears are used.
Lesson Length:
30-45 minutes
Содержание Education Simple Machines Deluxe GEARS
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