Question

What is the equivalent resistance of the circuit above?

• A. 20 ohms
• B. 10 ohms
• C. 5 ohms
• D. 2 ohms

Answer 1

The correct option is C 5 ohms

Equivalent resistance between $P$ and $Q$ $R_{PQ}=6+4=10$ ohms

Equivalent resistance between $A$ and $C$ $R_{AC}=5+5=10$ ohms

But $R_{PQ}$ and $R_{AC}$ are connected in parallel.

Thus equivalent resistance of the whole circuit $\frac{1}{R_{eq}}=\frac{1}{R_{PQ}}+\frac{1}{R_{AC}}$

$\therefore$ $\frac{1}{R_{eq}}=\frac{1}{10}+\frac{1}{10}$ $⟹R_{eq}=5$ ohms