Experiment 3 - Batteries in a Series Circuit III

And what if you turn one of the batteries around? Is the rule still true in that case? This you can just try it for yourself.

Build the shown circuit. You measure a total voltage of 7.5 volts. This is consistent with the rule. The individual voltages in a series circuit add up...

U_total = U₁ + U₂ = 9.0 V + (-1.5 V) = 7.5 V

Series Circuit of two opposing batteries. (Enlarge)

Circuit diagram of two opposing batteries in series.

Basically, the batteries have not "done" anything yet. No lamp was brought to light, no electric motor moved and nothing has been heated. The battery did not consume any of its stored energy.

The next experiment is about to change that...