Answer to Question #117365 in Electric Circuits for Asif Sultan

Question

What should be the equivalent resistance of it
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Answer 1

There are two possibilities.

If the actual connection has the following view:

then the equivalent resistance will be the resistance of two parallel resistors:

$$\dfrac{1}{R_{eq}} = \dfrac{1}{R} + \dfrac{1}{R} \Rightarrow R_{eq} = \dfrac{R\cdot R}{R + R} = \dfrac{R}{2}$$

If actual connection is the following:

Then the equivalent resistance will be $R_{eq} = 0$, for the middle wire has 0 resistance and all current will pass through it, regardless of the resistance R.

Answer. Req = R/2 or Req = 0 depending on the actual connection.