Manual

Project 151
Water Completes the Circuit
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Build the circuit as shown, leaving the ends of the red &
black jumper wires unconnected for now. Turn on the slide
switch (S1); the light tunnel (U30) should be off.
Place the loose ends of the red & black jumper wires into a
cup of water (but not distilled water), without them touching
each other. The light tunnel should be on now, because
water conducts electricity, completing this circuit. Don’t drink
any water used here.
Use the preceding circuit, but instead of placing the red &
black jumper wires in water, touch the metal part of each
with your fingers, using your body to complete the circuit.
Wet your fingers to get better electrical contact. The light
tunnel (U30) should be on, but brightness may vary.
Project 150
Human Conductor
Build the circuit as shown, leaving the ends of the red &
black jumper wires unconnected for now. Turn on the
slide switch (S1); the white LED (D6) should be off.
Place the loose ends of the red & black jumper wires
into a cup of water (but not distilled water), without them
touching each other. The white LED should be on now,
because water conducts electricity, completing this
circuit.
Try dissolving some salt in the water or using different
liquids, and see how the LED brightness changes. You
can also replace the white LED with the color LED (D8).
Don’t drink any liquids used here.
Use the preceding circuit, but
instead of placing the red & black
jumper wires in water, touch the
metal part of each with your
fingers, using your body to
complete the circuit. Wet your
fingers to get better electrical
contact. The white LED (D6)
should be on, but brightness may
vary.
Project 152
You Complete
the Circuit
Project 149 Liquid Conductor