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Attention ! L'hélice peut voler très vite et très haut. Ne vous penchez pas sur elle
afin d'éviter tout risque d'accident !
18. Flying propeller
Assemble the circuit as in the diagram. Attach the propeller. Press the button 14. When the
electric motor
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accelerates to a relatively high speed, suddenly release the button and the
propeller will take off.
(Attention: be careful!)
19. Changing the direction of the motor's rotation
Change the polarity of the motor's connection (change the positions of "plus" and "minus") and
attach the propeller. Press the button. You will see that the propeller is now rotating in the op-
posite direction. It can no longer fly, but it's now a powerful fan.
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20. Connecting the batteries in series
The diagram shows the batteries when they're connected in series. Here, the voltage of these
two 3-volt batteries is combined and is now equal to 6 volts. You can use the voltmeter to make
sure. If you're using 1.2 V batteries (1.2V) instead of 1.5 volt batteries, the total voltage is less.
Never stare at burning light-bulbs and LEDs for very long!
21. Reversing control circuit for the electric motor
Set up circuit and install the fan blades. Press the power button, and the fan blades will reverse.
Then, release the power button, use a magnet to engage the dry pipe, and the fan blades will
rotate inn the forward direction. Remove the magnet, press the power button again, and the
fan blades will reverse once more. (Note: do not close both the power button and the dry pipe
simultaneously; otherwise, it may damage the battery).
22. Light-Emitting Diode (LED)in parallel with light bulb
Close the switch, and both the LED and the light bulb will light up simultanneously. (When
connecting the LED to the circuit, it is necessary to include a current-limiting resistor in series.
The 17# LED is equipped with a small internal current limiting protective resistor when it leaves
the factory.)
Hot surface! Don't touch the lamp module
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