Hi how do you solve this problem? I am confused.
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Find \$R_{AB}\$, \$R_{CD}\$, \$R_{EF}\$, \$R_{AE}\$
I came up with this:
\$R_{A-B}\$ = 1 \$\Omega\$ ,
\$R_{C-D}\$ = 4 \$\Omega\$ ,
\$R_{E-F}\$ = 7 \$\Omega\$ ,
\$R_{A-E}\$ = 2 + 5 = 7 \$\Omega\$
Best Answer
Have you covered equivalent resistances? Essentially, it is a way to combine resistors in series or parallel until you get a single resistance, working your way from out to in.
Let's say you want to find \$R_{AB}\$.
First, your have a series combination \$R_5\$, \$R_6\$, and \$R_7\$. $$ R_{5,6,7} = R_5 + R_6 + R_7 = 18 \Omega $$
simulate this circuit – Schematic created using CircuitLab
Now you have a parallel combination between \$R_4\$ and \$R_{5,6,7}\$. $$ R_{4,5,6,7} = \frac{R_4 \cdot R_{5,6,7}}{R_4 + R_{5,6,7}} = 3.27 \Omega $$
simulate this circuit
You are almost done! Now, since you are looking for the equivalent resistance between A and B, you have a series combination for \$R_2\$, \$R_3\$ and \$R_{4,5,6,7}\$: $$ R_{2,3,4,5,6,7} = R_2 + R_3 + R_{4,5,6,7} = 8.27 \Omega $$
simulate this circuit
Last Step!
You have a parallel combination between \$R_1\$ and \$R_{2,3,4,5,6,7}\$: $$ R_{AB} = \frac{R_1 \cdot R_{2,3,4,5,6,7}}{R_1 + R_{2,3,4,5,6,7}} = 0.892\Omega $$