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Every gear has a job to do
Sprocket gears are set apart from each other and are
connected by a chain. Many bikes have a set of sprocket
gears which help you ride at an even pace, on any kind of
surface. Sprocket gears also pull roller coaster cars up the
first ramp of the ride.The chain has notches or pegs that fit
around the gears.When you turn one gear, the chain moves too, and it makes
the gear on the other end of the chain turn.These gears let you supply the
power in one place and have the power be used across a distance.
1
a.
Set up the Sprocket Bicycle Gear model
with the chain wrapped around the two
sets of small yellow Gears.Turn the pedal
and count the number of times the Wheel
turns. Record your answer.What is the
gear ratio for these Sprocket Bicycle
Gears? What is the Mechanical Advantage?
(Refer to the “What’s the Mechanical
Advantage” Reference Sheet.)
b.
Attach a cup with small weights to the
gray Rod with the Wheel. Measure the
force used to turn the pedals with
the K’NEX Rubber Band Scale. (Snap
the orange Connector at the bottom of
the Scale to the blue Rod on the pedal.)
Record your results.
2
a.
Add extra links to the Chain.Wrap the
Chain around the set of small Gears and
big Gears. Now put the pedals on the axle
with the small Gears. Put the wheel on the
axle with the big Gears. How does it feel
to turn the pedals?
b.
Repeat the process from Activity
1
.
Compare these results with your previous
results.Which set of Sprocket Bicycle
Gears need more force to lift the weight?
Why?
3
a.
Now switch the pedals to the axle with
the big Gears, and put the Wheel on the
axle with the small Gears.Turn the pedals.
How does it feel? Does the Wheel turn
faster or slower? Why?
b.
Repeat the process from Activity
1
.
4 Compare all your results.Why are the
gear combinations described as high and
low? How do your force and speed
measurements prove this? Which Gear
arrangement lets you ride fast with the
least force? Explain.
6 Why are sprocket gears a good choice for
a bicycle? Make a list of machines that
use sprocket gears. Explain why this gear
system is the best choice for these
machines.
1
2
3
4
5
The Sprocket
Bicycle Gear
STUDENT ACTIVITY SHEET
Содержание Education Simple Machines Deluxe GEARS
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