Question

The value of $i_1/i_2$ in the given diagram is:

• A. $\frac{P+Q}{R-S}$
• B. $\frac{R+S}{P+Q}$
• C. $\frac{P+Q}{R+S}$
• D. $\frac{R+S}{P-Q}$

Answer 1

The correct option is B $\frac{R+S}{P+Q}$

Resistors $(P$ & $Q)$ and $(R$ & $S)$ are in series

So,

equivalent resistance across $ABC=(P+Q)\Omega$

equivalent resistance across $ADC=(R+S)\Omega$

Currents in branch $ABC$ & $ADC$ are $I_1$ & $I_2$ respectively

we know,

Ohm's law, $V=IR$.

as across $AC$, voltage $(=E)$ is constant, we get :-

$I_1.R_{ABC}=I_2.R_{ADC}$

$\Rightarrow \frac{I_1}{I_2}=\frac{R+S}{P+Q}$