Question

what is the resistance b/w P and Q in fig.​

Answer 1

Explanation:

The 30 ohm resistor is in parallel with the 10 ohm resistor.

Net resistance of the two resistors = 1/(1/30 + 1/10) = 30/4 ohm

Now all the remaining resistors are in series connection.

Net resistance between points P and Q =

10 + 20 + 10 + 20 + 15/2

= 135/2 ohm