# Need help simplifying a ladder circuit

Discussion in 'Homework Help' started by maoyuusha, Feb 16, 2017.

1. ### maoyuushaNew Member

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We need to find the total resistance of this circuit but I'm not sure whether the circuit will shorten or not.
(I don't even have any idea on where I should start).

Can someone also give me tips and tricks in simplifying ladder type of circuits because I'm having problems when the circuits are not simple looking.
KhanAcademy only shows me how to solve simple looking circuits unlike this one.

(For the pic ^ is the total resistance 2 ohms?)

2. ### CiceroActive Member

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First picture is just all 3 resistors in parallel, drawn to trick you, so Rab = 1/3 ohms.

Yes, you're correct with the second pic being 2 ohms.

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3. ### maoyuushaNew Member

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In the second pic if the switch is closed will the total resistance still be equivalent to 2 ohms? Cause it doesn't seem like the switch will shorten the circuit.

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5. ### AnalogKidWell-Known Member

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In the second circuit, with all resistors of equal value, the switch does nothing. Rab is the same, open or closed.

ak

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6. ### specWell-Known MemberMost Helpful Member

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This thread neatly illustrates the importance of a well thought out and consistent schematic.

The questions are very clever.

spec

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