Understanding of how a light switch work

[adafus]

Hello everyone, i'm new here at the forum and i would like to start my first post with a rather simple question, how does these kind of light switch works? I know that there's something involving the passage of the electric current, but i would like to understand it better.

 

[danadakk]

Basically a circuit loop, one with energy source, and a load, is completed so current can flow.
Out from one battery electrode, thru the switch, then the load, and finally back to the other battery
electrode completing the circuit.

When switch is open its is an infinite resistance connection. And from ohms law we know
I = E / R, so if R is infinite then no current flows. If switch closed R ~= 0 (but load has some
resistance) so current flows.

Regards, Dana.

 

[Audioguru]

You show a "double throw" switch. The middle terminal connects to either the left terminal or the right terminal, never both at the same time.

 

[barry]

You show a "double throw" switch. The middle terminal connects to either the left terminal or the right terminal, never both at the same time.

OP is actually showing a switch that doesn't change, but the wiring to it does!

 

[Audioguru]

In the second wiring the light will never turn on when the switch position is changed.