Reading on a high resistance voltmeter, when a cell is connected across it, is $2.5 \mathrm{V}$. When the terminals of the cell are also connected to a resistance $5 \mathrm{\Omega }$ as shown in circuit of Fig.  the voltmeter reading drops to $2.0 \mathrm{V}$. Find the internal resistance of the cell. 

A $20 \mathrm{V}$ battery of internal resistance $1 \Omega$ is connected to three coils of $12 \mathrm{\Omega }, 6 \mathrm{\Omega }$ and $4 \mathrm{\Omega }$ in parallel, a resistor of $5 \mathrm{\Omega }$ and reversed battery (Emf $8 \mathrm{V}$ and internal resistance $2 \mathrm{\Omega }$ ) as shown in Fig. Calculate the current in the circuit.

A $20 \mathrm{V}$ Battery of internal resistance $1 \mathrm{\Omega }$ Is connected to three coils of $12 \mathrm{\Omega }, 6 \mathrm{\Omega }$ and $4 \mathrm{\Omega }$ In parallel, a resistor of $5 \mathrm{\Omega }$ And reversed battery (emf $8 \mathrm{V}$ And internal resistance $2 \mathrm{\Omega }$ ) as shown in Fig. Calculate  current in the resistor of $12 \mathrm{\Omega }$ coil 

A $20 \mathrm{V}$ battery of internal resistance $1 \mathrm{\Omega }$ is connected to three coils of $12 \mathrm{\Omega }, 6 \mathrm{\Omega }$ and $4 \mathrm{\Omega }$ in parallel, a resistor of $5 \mathrm{\Omega }$ and reversed battery (emf $8 \mathrm{V}$ and internal resistance $2 \mathrm{\Omega }$ ) as shown in Fig. Calculate potential difference across each battery. 

In the circuit shown in Fig: 5.143, find the charge on the capacitor plates 

Find the charges on the capacitors ${\mathrm{C}}_1,{\mathrm{C}}_2,{\mathrm{C}}_3,{\mathrm{C}}_4$ in the circuit shown in Fig.

Calculate the current through the $3 \mathrm{\Omega }$ Resistance and the power developed in the entire circuit shown in the figure, Fig. The emf of the battery is $1.8 \mathrm{V}$ And its internal resistance is $\frac{2}{3} \mathrm{\Omega }$

A distant telephone, whose resistance is $300 \mathrm{\Omega }$ is connected to the exchange, $10 \mathrm{km}$ away, by a pair of telephone wires whose resistance singly, is $5 \mathrm{\Omega }$ per $\mathrm{km}$. A twig falls across the wires at a certain point, producing the effect of a resistance $R$ connected between the wires at the point. Measurements made at the exchange show a resistance between the terminals of the line of $130 \mathrm{\Omega }$. Which rises to $160 \mathrm{\Omega }$ when the distant telephone is disconnected. How far from the exchange in the fault to be found and what is the value of $\mathrm{R}$?