# Voltage across resistors in series and parallel

So I must be missing some crucial knowledge in my knowledge of electrostatics because I simply don't understand how this works. I'm given a circuit like this:

[PLAIN]http://img3.imageshack.us/img3/8730/circuiti.png [Broken]

and I find out the voltage across bulb B is the same as that across the 10 ohm resistor.

I was under the impression that, since we know V = IR and we know the current across B is the same as the current across the 10 ohm resistor the Voltage would be different assuming B has a resistance other than 10 ohms. What am I missing here?

Last edited by a moderator:

Doc Al
Mentor
The voltage is the same, not necessarily the current. Branches in parallel have the same voltage.

The voltage is the same, not necessarily the current. Branches in parallel have the same voltage.

Would that also apply to two resistors in series? If I simply had a battery with two resistors in series would their voltage be equal regardless of whether or not their resistors were equal?

Doc Al
Mentor
Would that also apply to two resistors in series? If I simply had a battery with two resistors in series would their voltage be equal regardless of whether or not their resistors were equal?
Things in parallel have the same voltage; things in series have the same current.