Question

In a battery five dry cells each of 1.5 volt have internal resistance of $0.2,0.3,0.4,0.5$ and $0.6\Omega$ are present in series. The battery is connected to a $1\Omega$ resistance. Identify the correct statement (s) :

• A. Current in the circuit will be $2.5A$
• B. Current in the circuit will be $1.5A$
• C. On short circuiting the battery $3.75A$ current will flow
• D. Both $\left(A\right)$ and $\left(C\right)$

Answer 1

The correct option is D Both $\left(A\right)$ and $\left(C\right)$

$R_{eq}=r_1+r_2+r_3+r_4+r_5+R=0.2+0.3+0.4+0.5+0.6+1$

$R_{eq}=3\Omega$

$$E_{eq}=5E=7.5V$

$I=\frac{E_{eq}}{R_{eq}}=\frac{7.5}{3}$

$⟹I=2.5A$

When battery is shorted , no current flows through $R$.

Equivalent resistance becomes $R_{eq}=r_1+r_2+r_3+r_4+r_5$

$⟹R_{eq}=3\Omega$

Current=$I=\frac{E_{eq}}{R_{eq}}$

$⟹=I=\frac{7}{2}=3.5A$

Answer-(D)