Question

The equivalent resistance between points $A$ and $B$ is:

• A. $45\Omega$
• B. $135\Omega$
• C. $\frac{45}{2}\Omega$
• D. $\frac{65}{2}\Omega$

Answer 1

The correct option is C $\frac{45}{2}\Omega$

Potential is same on all points of short circuited wire. Let mark the point having same potential as $x$ and $y$.


Resistance $25\Omega$, $50\Omega$ and $50\Omega$ are in parallel becuase all three are connected across $x$ and $y$.


Now, all the three resistances are in series combination, because current passing through them will be same if a battery is connected across $A$ and $B$.

$R_{eq}=2+\frac{25}{2}+8=\frac{45}{2}\Omega$