Data Sheet

-21-
9. Newton’s Second Law of Motion
Remove the cap (59) that is on the fan blade (60). Hold the press switch (61) for ten seconds. Release the press switch
(61) and the ying saucer should take off (Caution! Never let it y near your face!). If the fan does not y, make sure the
batteries are fresh, the motor (95) is in the correct direction, and give the fan a tap from underneath with the top of your
ngernail. This circuit demonstrates Newton’s Second Law of Motion: acceleration is produced when a force acts on a
mass. In this case, air pressure under the fan blade forces it to rise.
10. Launching versus Latching Forces
Replace the press switch (61) with the switch (62) and turn the motor (95) on. Wait for the motor (95) to reach top
speed. If the fan does not launch, then the force in the motor latch is greater than the air pressure. Press the switch
(62) again and the fan should launch. If the fan does not y, make sure the batteries are fresh, the motor is in the correct
direction, and give the fan a tap from underneath with the top of your ngernail.
11. Magnet-controlled Flying Saucer
Replace the press switch (61) with the reed switch (83) and move the magnet (7) towards the reed switch (83). Wait for
a few seconds, then move the magnet (7) away to launch the saucer. A reed switch is typically made from two or more
ferrous reeds (thin strips) encased within a small glass tube-like envelope, which become magnetized and move together
or separate when a magnetic eld is moved towards the switch.
Reminder: Remove the shaft cap (59) before
launching the ying saucer.
WARNING: Moving parts. Do not touch
the fan or motor during operation. Do
not lean over the motor.
!
1st level