I need help installing a switch for a garbage disposal and a dish washer. I want one of them to be hot and the other to be toggled by the switch. I see diagrams all over but they are showing it ran with four wires and I only have 3. Also it will be in a line with two other plugs. So my lingo of this stuff isn't up to par! I have a junction box for 3 spots so it will have two spots with outlets then the switch. then i will drop the new switch under the sink.

So from what I understand voltage remains the same in a parallel circuit and current remains the same in a series circuit. If I am correct then the following would be true? Incandescent Light Bulb Volts = 4.9 Amps = .3 Resistance = 16.3 Watts = 1.47 Power Source AC->DC Wall Adapter Volts = 5.0 Amps = 7.0 Watts = 35 If hooked up in a series I could use 23 bulbs (7 amps divided by .3 amps)? I guess what I don't get is that if this is true I couldn't hook up 2 bulbs to the same adapter in a series because there is only 5 volts of power, correct? If I wanted to run them in a series I would need a 100v adapter rated at .3 amps?