What is the current in this circuit?

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The discussion revolves around calculating the current in a circuit with two batteries and a resistor. The first battery has an EMF of 15 V and internal resistance of 9 ohms, while the second has an EMF of 9 V and internal resistance of 4 ohms. The circuit configuration causes one battery to drive current clockwise and the other counterclockwise. Applying Kirchhoff's rule and Ohm's law is essential for solving the problem, particularly considering the internal resistances of the batteries. The correct current flowing in the circuit is approximately 0.0952 A.
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Ok, I already got all 6 points off on this homework problem:( but it might be on the test tomorrow. I know what the answers should be. He says you apply Kirchoff's rule, I've tried, and I don't get the right answers. Help! if you can get (a) I can get the rest.


Two batteries and a 50-ohm resistor are connected in a single, simple loop. The first battery has an EMF of 15 V and an internal resistance of 9 ohms. The second battery has an EMF of 9 V and an internal resistance of 4 ohms. The circuit is connected in such a way that first battery is trying to drive current clockwise in the circuit while the second battery is trying to drive current counterclockwise.

For questions (a) through (f) below, enter each answer as a positive number.

(a) How much current flows in the circuit?

0.0952 (real answer)
 
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Draw a picture and use Ohm's law. The sum of the voltages around the loop will equal 0.
 
hmmm

Let's say I don't know what that is... I drew a picture. Ohm's law is v=ir but what do I do about the internal resistance, or that one's pushing current one way, and one's pushing current the other way...
 
That's the sweet thing about V=IR. Internal resitance, and the Source Voltage tells you how much Current the source is developing, does it not?
 

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