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HELP! Isaac Physics Equivalent Resistors Part b

I need help on part B of Equivalent resistors on Isaac Physics please. I've tried re-drawing the circuit across a straight line from points A to B and re-drawing each junction, and then I found the equivalent resistance to be 3.2 to 2sf but its wrong.
Original post by Io0
I need help on part B of Equivalent resistors on Isaac Physics please. I've tried re-drawing the circuit across a straight line from points A to B and re-drawing each junction, and then I found the equivalent resistance to be 3.2 to 2sf but its wrong.


If you could provide an example of some of the working you have done so far to tackle this problem that would be helpful in knowing how best to assist you.
Reply 2
Original post by Joseph McMahon
If you could provide an example of some of the working you have done so far to tackle this problem that would be helpful in knowing how best to assist you.

This will be quite the challenge to explain but let me try

So I drew two 5 and one 12 ohm resistor in series. Across the 12 ohm resistor I had a 6 ohm resistor. Across the 5,5,12 AND 6 ohm resistor I had a 10 ohm resistor and across all the resistors I had a 7 ohm resistor. Using the equations for resistors in series and in parallel I got 3.2 ohms as my equivalent resistance to 3sf. Thanks for taking the time to look at my question and bother responding, I appreciate it!
In the diagram (hint 3) note that DC (second rung on the ladder) is a short, which simplifies the calculation somewhat.
It would help if youd upload a sketch of your circuit.
https://isaacphysics.org/questions/equivalent_resistors?stage=all

i believe this is the question.

you don't need to worry about the resistance of the circuit below the 5 ohm resistor. This is because no current will flow into the next 5 ohm resistor connected in series, as it is essentially a short circuit. So to find the equivalent resistance, ignore the bottom half of the circuit
Reply 5
(Original post by Joseph McMahon)What answer did you get for part A? (Assuming you got that part of the question without issue)

I got 4.0
Reply 6
Original post by iTsJames123
https://isaacphysics.org/questions/equivalent_resistors?stage=all

i believe this is the question.

you don't need to worry about the resistance of the circuit below the 5 ohm resistor. This is because no current will flow into the next 5 ohm resistor connected in series, as it is essentially a short circuit. So to find the equivalent resistance, ignore the bottom half of the circuit

Yup that's the question there. Thanks! I'll attempt it now

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