# Terminal voltage for 2 batteries

1. Oct 28, 2009

1. The problem statement, all variables and given/known data

two batteries A and B are connected in parallel, and an 80 ohm resistor is connected across the battery terminals. the e.m.f and the internal resistance of battery A are 100V and 5ohms respectively, and the corresponding values for battery B are 95V and 3ohms respectively.

2. Relevant equations

find (a) the value and direction of the current in each battery and (b) the terminal voltage

3. The attempt at a solution

I've done part (a) but i'm stuck on part (b). i know the answer is 94.66V from looking at the back of the text book but how do i get this answer? please help!!!

2. Oct 28, 2009

### Delphi51

From (a) you know the current through the 80 ohm resister, so you can use V = IR to find the voltage on the whole parallel system including the two batteries.

3. Oct 28, 2009

oh so is it the current through battery A, B and the resistor, multiplied by the resistor?

4. Oct 28, 2009

### Delphi51

The current through the resistor is the sum of the two currents from the batteries. That's the "sum of the currents into a node is zero" rule.

5. Oct 28, 2009