The resistors in (Figure 1) are all 1.2 Ω. What is the equivalent resistance between points a and b?
- billrussell42Lv 71 month ago
1 & 2 in series equal 2.4
that in parallel with 3 is 2.4•1.2 / (2.4+1.2) = 0.8
that is series with 4 is 2
that in parallel with 5 is 2•1.2 / (2+1.2) = 0.75
that is series with 6 is 1.2+0.75 = 1.95 Ω (ans)
- ?Lv 71 month ago
Let's call the resistors across the top A, B, C and then the vertical ones D, E, F. Obviously A is in series with the rest of the arrangement. Then you could regard D as parallel to the combo BCEF. In that combo BCEF, the B is clearly in series with CEF, while the E is parallel to CF.
OK, so the resistance of CEF is 1.2||2.4 = 0.8. Put that in series with B, and you get 2 ohms exactly. Put that in parallel with D and you get
1.2||2.0 = 0.75 ohms exactly. Put that in series with A and you get 1.95 ohms exactly.
So my answer is 1.95 ohms.