Find equivalent resistance of the network in Fig. between points (i) A and B and (ii) and C.

Explanation

(i) The `100 Omega` and `30Omega` resistors are connected in parallel between points A and B. The equivalent resistance between A and B is
`R_(1)=(10xx30)/(10+30)" ohm "=7.5Omega`
(ii) The resistance `R_(1)` is connected in series with resistor of `7.5Omega`, hence the equivalent resistance between points A and B is C is, `R_(2)=(R_(1)+7.5)" ohm "=(7.5+7.5)" ohm "=15Omega.`