Positive and negative

[PhiI2e]

when you have 2 black wires coming off an Ac adaptor, which one is positive and which is negative? One usually has a white stripe running down it or writing down it.

 

[sohcrates]

what kind of AC adapter are you talking about?

 

[SuperSix]

There's no positive/negative with A/C current. If it's an A/C adapter brick, it more than likely is outputting DC, and if it is, you will have to use a meter to tell which is which. It should have the output listed on the back of the brick.