Total net voltage applied to lamps

Thread Starter


Joined Feb 5, 2007
Hey guys, I'm doing a HW problem where I'm told to find the total net voltage being applied to 3 identical lamps. Here's my crude drawing:

Okay, I know that +6V is coming in from above to the lamps and -6V is coming in from the bottom to the lamps. So, how do I find out what the "total net voltage applied to the lamps" is? I would guess 6 V, but I'm not sure due to the wording of the problem. I know that it is 6V -> lamp -> 2V -> lamp -> -2V -> lamp -> -6V.

MUCH thanks in advance!


Joined Jun 30, 2006
You have a 12v supply running 3 equal loads. :)

That center tap inbetween the batteries is confusing. It's not the lowest potential point and it's just hanging there.


Joined Feb 10, 2007
Ground can be anywhere... and from what I understand (correct me if I'm wrong), if you're using negative potential you are simply referencing ground from a negative position as opposed to 0V.

-6V to +6V = 12V

In this case it just looks like two 6V sources in series, which also gives 12V... which will apply 4V to each lamp.