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Clearly Solar Car User Guide 60024 V0413
P.O. Box 1708 • Pittsburg, KS 66762
shop.pitsco.com
Toll-Free Orders 800-835-0686
Switching Gears
You can also try different gear combinations on the Clearly Solar Car. The setup in these instructions has the 10-tooth
pinion gear connecting to a 40-tooth gear that – via the small axle – turns the 20-tooth gear. This gear moves the
50-tooth gear that is attached to the back axle and spins the wheels.
You can also remove a back wheel and switch the back axle so the 50-tooth gear is on the left side. Then adjust the
motor mount so the 50-tooth gear can engage with the 40-tooth gear that is connected to the pinion gear.
Tip: If you make a habit of switching the back axle, the axle hole will become loose over time. If this happens, you
can insert a thread or two into the axle hole on the hub before placing the tires back on. This will give you a tighter
fit.
Activity: Series vs Parallel Circuits
1. Outdoors on a sunny day, measure and mark a distance of 10 feet (3.05 meters) in which to test the car. Arrange
the solar panel connections on the car for a series circuit.
2. Place the car at the starting line and let it go. Using a stopwatch, time how long it takes the car to travel the
distance.
3. Now switch the connections to a parallel circuit. Again, place the car at the starting line and time how long it
takes to travel the distance. Looking at the results, which type of circuit works better for speed? Considering
the information on page 2, discuss why this is true. Then, discuss what advantages there might be for the other
connection if it isn’t faster.
4. Set up a 20-foot (6.10 m) course and redo the experiment. Did a longer track make a difference in the overall
performance of either circuit?
5. Calculate the ratio between the performance (in terms of speed) of the series and parallel circuit tests, first for
the 10-foot test (3.05 m) and then for the 20-foot test (6.10 m).
6. Set up an inclined lane and redo the experiment. Explain the results.
For more activity ideas for this kit, visit shop.pitsco.com, search for the Clearly Solar Car Kit, and click the Activity tab.
