# Resistors in Series

1. Oct 4, 2005

### Midas_Touch

|------A------|
|..................* R2
- Vs..............|B
-..................|
|..................* R1
|------C----- |

Assuming that the above is a circuit (sorry for the bad drawing, ignore the dots), what would be Ia, Ib, Ic (currents), Va, Vb, Vc (voltages)? Initially, I thought that the current and the voltage would be the same at all points.

I know that Req is equal to the sum of R1 and R2 (resistance). So would Ia be Vs/(R1*R2)? Would Ib be Vs/R2? and Ic, Vs/R1?

For the voltages, I think that it is equal to Vs at points A,B,C. But, I am not sure.

I'd appreciate some feedback. Thanks.

Last edited by a moderator: Oct 4, 2005
2. Oct 4, 2005

### Integral

Staff Emeritus
In a series circiut the current is the same at all points, not the voltage. Use Ohms law to find the voltage at each point, given the constant current. Your total voltage drop should equal the source voltage.

3. Oct 4, 2005

### Ouabache

Interestingly you are using two correct concepts, but not applied to the correct variable.

It is the voltage (potential) that starts off at a value (Vs) and in a series circuit, drops some amount through each component, until it reaches its lowest value (typically ground = 0v).

The other variable current, in a series arrangement, does not drop but stays the same through each component.

This will be different in a parallel arrangement, and I will let you figure that one out.. Applying what I gave you above, try this one again..

Last edited: Oct 4, 2005
4. Oct 4, 2005

### Midas_Touch

How about if R2 was parallel to R1? Would the current still be the same and the voltage be different at points around the circuit?

5. Oct 4, 2005

### Ouabache

See my last post, and you should be able to deduce your answer.

6. Oct 4, 2005

### Integral

Staff Emeritus
If R2 were parallel to R1 then it would not be a series circuit would it? Why do you expect a parallel circuit to behave the same as a series?