Elenco Green Projects - Manual (Page 36)

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Build the circuit and place the wind fan on the motor (M4). Set the
meter (M6) to the 5V setting. Connect the black jumper wire between
the meter and 5-snap wire. Connect one end of the red jumper wire
to the pivot stand; leave the other end loose. Set the slide switch (S5)
to position B. Place the solar cell (B7) in bright sunlight or near an
incandescent lamp. If the light is bright enough, the LEDs (D1 & D5)
will light and the fan will spin. You may need to give the fan a push to
get it started.
Project #47 Voltage Order
C
B
D
A
F
E
5V
This circuit has the battery (B4) and solar cell producing voltage to
push electric current through the LEDs and motor. Although the
meter is set to the 5V scale, a resistor in the pivot stand changes
the voltage scale to 10V, so double the voltage you read on the
meter.
A. Connect the loose end of the red jumper wire to the snap
marked A to measure the voltage between there and the black
jumper wire’s location. It is just the voltage across the battery.
B. Move the end of the red jumper from point A to point B, to see
how much the voltage is increased by the solar cell.
C. Move the end of the red jumper from point B to point C, to see
how much the voltage changed across the switch.
D. Move the end of the red jumper from point C to point D, to see
how much the voltage was reduced as it pushed current through
the yellow LED.
E. Move the end of the red jumper from point D to point E, to see
how much the voltage was reduced as it pushed current through
the motor.
F. Finally, move the end of the red jumper from point E to point F,
to see how much the voltage was reduced as it pushed current
through the red LED.
Part 2: Take the end of the black jumper wire off the 5-snap wire.
Place the loose ends of the red and black jumper wires across any
two points in the circuit to measure the voltage change between
them (remember that the meter only measures positive voltages).
See projects 1 & 3 if you need to recharge the battery (B4).