What is the Equivalent Resistance in this Circuit?

AI Thread Summary
The discussion revolves around calculating the equivalent resistance in a specific circuit where an ammeter reads zero. Participants emphasize that the branch with the ammeter can be treated as a short or open circuit due to the lack of current. The concept of the Wheatstone Bridge is introduced, highlighting its balancing condition as relevant to the problem. To find the equivalent resistance, it's suggested to either remove the ammeter or replace it with a conductor. The conversation focuses on applying the equivalent resistance formula to solve the circuit effectively.
keemosabi
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Homework Statement


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Homework Equations





The Attempt at a Solution


I really just don't know. I understand how equivalent resistance works, but I just don't get this question. Please ignore the marks I have on the page.
 
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Since the ammeter reads zero, that branch can be taken as short circuit or open circuit.
Now apply equivalent resistance formula to find R.
 
rl.bhat said:
Since the ammeter reads zero, that branch can be taken as short circuit or open circuit.
Now apply equivalent resistance formula to find R.
Sorry, but I'm not really sure what you mean by that.
 
keemosabi said:
Sorry, but I'm not really sure what you mean by that.

Have you heard about the Wheatstone Bridge? What is the balancing condition of the bridge?
When there is no current in the ammeter, either remove the ammeter from that branch, or replace it by a conductor and find the equivalent resistance of the circuit.
 
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