Decreasing Saucer Lift

Project Number: 12

Parts Needed For Circuit: L1

OBJECTIVE: To show how voltage affects the speed of a DC motor and can decrease the lift of the saucer.

Description: Change the circuit in Project #11 by adding the lamp (L1) in series with the motor as shown in the diagram on the left. When you place the lamp in series with any electronic device, it will draw less current because it adds resistance. In this case, the lamp in series reduces the current through the motor, and that reduces the top speed of the motor. Close the slide switch (S1), and wait until the fan reaches maximum speed. Open the switch and observe the difference in the height due to the lamp. In most cases, it may not even launch.