Question

Consider a network of resistors with each branch of resistance $R$. The equivalent resistance between $A$ and $E$ if

• A. the figure is as shown is $\frac{2R}{3}$
• B. the wire BD is removed is $\frac{2R}{3}$
• C. the wire AD is removed is $\frac{7R}{8}$
• D. the wire AC and AB is removed is R

Answer 1

Answer: (A), (B), (C)

the wire AD is removed is $\frac{7R}{8}$

=$\frac{R}{2}+\frac{\frac{3R}{2}\times \frac{R}{2}}{\frac{3R}{2}+\frac{R}{2}}=\frac{7R}{8}$
$\to R+\frac{R}{2}=\frac{3R}{2}$