The equivalent resistance of the given circuit between the terminals A and B is [Figure: a ladder between a top rail ending at A and a bottom rail ending at B. At the far left a plain wire joins the top and bottom rails, with a 5 Ω resistor just to its right also joining the rails. Along the top ra…

Question

The equivalent resistance of the given circuit between the terminals A and B is [Figure: a ladder between a top rail ending at A and a bottom rail ending at B. At the far left a plain wire joins the top and bottom rails, with a 5 Ω resistor just to its right also joining the rails. Along the top rail: 2 Ω, then a node where a vertical 2 Ω goes to the bottom rail, then another 2 Ω, then two vertical 3 Ω resistors joining the top rail to the bottom rail, then terminal A.]

Accepted Answer

(4) 1 Ω. The plain wire at the far left shorts the 5 Ω, so it carries no current. First top 2 Ω now runs from the middle node straight to the bottom rail: in parallel with the vertical 2 Ω gives 1 Ω. Add the second top 2 Ω: 1+2=3 Ω between A and B. This 3 Ω is in parallel with the two 3 Ω resistors: 3∥3∥3=1 Ω R_AB=1 Ω

Step-by-step solution

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