Voltage Order

Project Number: 47

Description: 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 the 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.

Snappy: This circuit has the battery (B4) and the solar cell producing voltage to push electric current through the LEDs and the 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 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 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 has 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 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 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 through the red LED. Part 2: Take the end of the black jumper wire off the 5-snap wire. Pace 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).