Question

Calculate the equivalent resistance between A and B from the diagram given.

Answer 1

The EG, GH and FH resistances are in series:

R1=20+20+20
R1=60ohms

R1 and EF are in parallel:

$\frac{1}{60} + \frac{1}{40} = \frac{1}{r2}$
R2=24ohms

Now CE, R2 and DF are in series:

R3=24+40+40
R3=104ohms

Now, CD and R3 are in parallel:
$\frac{1}{104} + \frac{1}{40} = \frac{1}{r4}$
R4=260/9 ohms

Now, AC, R4 and BD are in series:
260/9 +20+20=Net Resistance

Net resistance=620/9 ohms = 68.889ohms.

Corrections are welcome.