Cells in Series and in Parallel

Two cells of emf  $E_1$  and  $E_2$  and internal resistance  $r_1$  and  $r_2$ , are connected in parallel with each other. Obtain expressions for the equivalent emf and equivalent internal resistance of this parallel combination.

If $M, N, O, P$ and $Q$ are in the increasing order of their standard potentials in standard conditions of their standard half cells, then by combination of which two half cells maximum cell potential will be obtained?

In the circuit diagram shown in figure given below, the current flowing through resistance $3 \mathrm{\Omega }$ is $\frac{x}{3} \mathrm{A}$. The value of $x$ is ________.

In the circuit of two cells, each of emf $E$ but different internal resistances are connected in series as shown in the diagram. Determine the external resistance $R$ in terms of internals resistances $r_1$ and $r_2$, such that potential drop across the cell ${\mathrm{E}}_1$ is zero.

Explain the equivalent emf.

If $\mathrm{n}$ cells each of emf $\mathrm{\epsilon }$ and internal resistance $\mathrm{r}$ are connected in parallel, then the total emf and internal resistance will be

The emf of a storage battery is $90 \mathrm{V}$ before charging and $100 \mathrm{V}$ after charging. When charging began the current was $10 \mathrm{A}$. What is the current at the end of charging if the internal resistance of the storage battery during the whole process of charging may be taken as constant and equal to $2 \mathrm{\Omega }$? 

In the shown circuit all cells are ideal. Let potential at point $B$ and $D$ be $V_B$ and $V_D$ respectively. Then $V_B-V_D$ is equal to

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The current through the $5 \Omega$ resistance connected across $AB$ as shown in the given circuit is

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Ten identical cells each of potential $E$ and internal resistance $r$, are connected in series to form a closed circuit. An ideal voltmeter, connected across three cells, will read

The current '$i$' in the circuit shown in the figure is

In the above circuit the current in each resistance is

The combination of two identical cells, whether connected in series or parallel combination provides the same current through an external resistance of $2 \mathrm{\Omega }$. The value of internal resistance of each cell is

Four cells each of emf $E$ and internal $r$ are connected in series. If polarity of one cell is reversed, then the terminal voltage across this cell is

One electric cell (having emf of $2 \mathrm{V}$ & internal resistance of $0.1 \mathrm{\Omega }$) and other electric cell (having emf of $4 \mathrm{V}$ and internal resistance of $0.2 \mathrm{\Omega }$ ) are connected in parallel to each other. Then its equivalent emf will be $\mathrm{V}$

Four cells of emf $1\mathrm{V},2\mathrm{V},3\mathrm{V}$ and $4\mathrm{V}$ are connected in parallel as shown. If their internal resistances are respectively $1\mathrm{\Omega },1\mathrm{\Omega },1\mathrm{\Omega }$ and $2\mathrm{\Omega }$, then the current through the external load resistance $R$ is

Explain cells in series and cells in Parallel.

For the circuit shown in the figure calculate $V_{AD}, V_{EA}\text{ and }{V}_{FC}$.

Two cells having the internal resistance $0.2\mathrm{ }\mathrm{\Omega }$ and $0.4\mathrm{ }\mathrm{\Omega }$ are connected in parallel. The voltage across the battery terminals is $1.5 \mathrm{V}$. The emf of first cell is $1.2 \mathrm{V}$, the emf of second cell is (in volt) $E$. Write the value of $\left[E\right],$ where $\left[ \right]$ is the greatest integer function.

A battery consists of a variable number ($n$) of identical cells, each having an internal resistance $r$ connected in series. The terminal of the battery is short-circuited. A graph of current versus the number of cells will be as shown in figure.