Question

Eight resistors are connected as shown, find the equivalent resistance, if each resistor is of 2 ohm.​

Answer 1

Answer:

The correct option (B) (8r/15) Explanation: Here r & r are in series when is further parallel with r ∴ RBC = (r + r) || r = 2r || r = {(2r × r)/(2r + r)} = (2r2/3r) = (2/3)r RBC = RAD = (2/3)r hence circuit can be drawn as

∴ RAD = (2r/3) || {r + r + (2r/3)}

= (2r/3) || {2r + (2r/3)}

= (2r/3) || (8r/3)

= [{(2r/3) × (8r/3)}/{(2r/3) + (8r/3)}]

= {16r2/9} × {3/10r}

= (16/30)r = (8/15)r

Eight identical resistances r each are connected as shown find equivalent resistance between A and D.