Question

In the figure find the effective resistance of the network between P and Q.

• A. $\frac{7}{2}R$
• B. $\frac{5}{2}R$
• C. $\frac{5}{3}R$
• D. $\frac{7}{3}R$

Answer 1

The correct option is B $\frac{5}{2}R$

Here we see that first there are two series combination of three $R$ resistors whose equivalent resistance is $3R$.

Now, the two $3R$ resistors are in parallel combination giving resistance $\frac{3R}{2}$.

This resistance $\frac{3R}{2}$ is in series combination of $R$.

Hence equivalent resistance is $R+\frac{3R}{2}=\frac{5R}{2}$

Answer-(B)