Question about reversed sources. (in circuits)?

Question

What happens to the voltage and current when you have two sources in series, and one of them is reversed. Why.

I really don`t understand this, I would really appreciate if someone could explain it to me.

What do you mean by + = +

And lets say we have four sources and only 1 is reversed, then what happens.

Answer 1

For voltage sources in series, the voltage will just add. If one of the voltage sources is reversed in polarity, then its voltage will subtract.

For current sources, you should not hook these up in "series" without any other load, as they will attempt to burn each other up. You can hook them up in parallel and their currents will add or subtract (depending on their polarity).

You also should not connect voltage sources in parallel unless they are set at exactly the same voltage, or there is a load resistor in between (if you put them in parallel with different voltages, they will both try to produce whatever current they can to hold the node to their set voltages - one will eventually win. The other will likely be damaged).

Answer 2

If you have two DC sources of equal voltage, and you reverse one, they cancel out. The current goes to 0 because there is no net voltage to drive it. If the two are not equal, the net voltage will be the difference between the two, with larger source determining the direction of the current flow. This hookup is not good for the smaller source.

Four equal sources connected in series will produce a net voltage of 4V. Reverse one of them, and it cancels one of the remaining 3, resulting in a net voltage of 2V.

Answer 3

the net current will be Zero, because each source will cancel the other source; since their polarities are different ( for instance the first current will flow clockwise and the other flows counter clockwise and if they have the same magnitude - value - they will eliminate- cancel each other)