# Current in a ciruit

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

The circuit is given as in the attachment. All resistors have known resistance and the inner resistance of the ammeter in known. The current which is measured by the ammeter is known. What is the current at the point T?

**2. Relevant equations**

Ohm’s law: V=IR. Also at each junction, I_{in}=I_{out}.

**3. The attempt at a solution**

Let R_{0} be the resistance of the ammeter, I_{1} be the current at the point T, I_{2} be the current at resistor R_{2} and I_{A} be the current at ammeter. It follows that I_{A}R_{0}=I_{2}R_{2}, from which I_{2} follows. Then I_{1}=I_{2}+I_{3}.

That is what I think is true. But, given the values of resistances of all resistors which I didn’t use in the calculation, I start to wonder if I miss something. Am I right or wrong?

http://ift.tt/1jZL7uk

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