04. Cells, Internal Resistance and Cell Combination, Thermocouple
Current Electricity

152536 The voltage $V$ and current $I$ graph for a conductor at two different temperatures $T_{1}$ and $T_{2}$ and shown in the figure. The relation between $T_{1}$ and $T_{2}$ is :

1 $\mathrm{T}_{1}>\mathrm{T}_{2}$
2 $\mathrm{T}_{1}\lt\mathrm{T}_{2}$
3 $\mathrm{T}_{1}=\mathrm{T}_{2}$
4 $\mathrm{T}_{1}=\frac{1}{\mathrm{~T}_{2}}$
Current Electricity

152537 A battery of emf $E$ has an internal resistance $r$. $A$ variable resistance $R$ is connected to the terminals of the battery. A current $i$ is drawn from the battery. $V$ is the terminal potential difference. If $R$ alone is gradually reduced to zero, which of the following best describes $i$ and $V$ ?

1 $\mathrm{i}$ approaches zero, $\mathrm{V}$ approaches $\mathrm{E}$
2 i approaches $\frac{\mathrm{E}}{\mathrm{r}}$, V approaches zero
3 i approaches $\frac{E}{r}$, V approaches $E$
4 i approaches infinity, $V$ approaches $\mathrm{E}$
Current Electricity

152538 Two cells of emf $E_{1}$ and $E_{2}$ are joined in opposition (such that $E_{1}>E_{2}$ ). If $r_{1}$ and $r_{2}$ be the internal resistances and $R$ be the external resistance, then the terminal potential difference is :

1 $\frac{E_{1}-E_{2}}{r_{1}+r_{2}} \times R$
2 $\frac{E_{1}+E_{2}}{r_{1}+r_{2}} \times R$
3 $\frac{E_{1}-E_{2}}{r_{1}+r_{2}+R} \times R$
4 $\frac{\mathrm{E}_{1}+\mathrm{E}_{2}}{\mathrm{r}_{1}+\mathrm{r}_{2}+\mathrm{R}} \times \mathrm{R}$
Current Electricity

152539 Four identical cells of emf $E$ and internal resistance $r$ are to be connected in series. Suppose, if one of the cell is connected wrongly, the equivalent emf and effective internal resistance of the combination is :

1 $2 \mathrm{E}$ and $4 \mathrm{r}$
2 $4 \mathrm{E}$ and $4 \mathrm{r}$
3 $2 \mathrm{E}$ and $2 \mathrm{r}$
4 $4 \mathrm{E}$ and $2 \mathrm{r}$
Current Electricity

152536 The voltage $V$ and current $I$ graph for a conductor at two different temperatures $T_{1}$ and $T_{2}$ and shown in the figure. The relation between $T_{1}$ and $T_{2}$ is :

1 $\mathrm{T}_{1}>\mathrm{T}_{2}$
2 $\mathrm{T}_{1}\lt\mathrm{T}_{2}$
3 $\mathrm{T}_{1}=\mathrm{T}_{2}$
4 $\mathrm{T}_{1}=\frac{1}{\mathrm{~T}_{2}}$
Current Electricity

152537 A battery of emf $E$ has an internal resistance $r$. $A$ variable resistance $R$ is connected to the terminals of the battery. A current $i$ is drawn from the battery. $V$ is the terminal potential difference. If $R$ alone is gradually reduced to zero, which of the following best describes $i$ and $V$ ?

1 $\mathrm{i}$ approaches zero, $\mathrm{V}$ approaches $\mathrm{E}$
2 i approaches $\frac{\mathrm{E}}{\mathrm{r}}$, V approaches zero
3 i approaches $\frac{E}{r}$, V approaches $E$
4 i approaches infinity, $V$ approaches $\mathrm{E}$
Current Electricity

152538 Two cells of emf $E_{1}$ and $E_{2}$ are joined in opposition (such that $E_{1}>E_{2}$ ). If $r_{1}$ and $r_{2}$ be the internal resistances and $R$ be the external resistance, then the terminal potential difference is :

1 $\frac{E_{1}-E_{2}}{r_{1}+r_{2}} \times R$
2 $\frac{E_{1}+E_{2}}{r_{1}+r_{2}} \times R$
3 $\frac{E_{1}-E_{2}}{r_{1}+r_{2}+R} \times R$
4 $\frac{\mathrm{E}_{1}+\mathrm{E}_{2}}{\mathrm{r}_{1}+\mathrm{r}_{2}+\mathrm{R}} \times \mathrm{R}$
Current Electricity

152539 Four identical cells of emf $E$ and internal resistance $r$ are to be connected in series. Suppose, if one of the cell is connected wrongly, the equivalent emf and effective internal resistance of the combination is :

1 $2 \mathrm{E}$ and $4 \mathrm{r}$
2 $4 \mathrm{E}$ and $4 \mathrm{r}$
3 $2 \mathrm{E}$ and $2 \mathrm{r}$
4 $4 \mathrm{E}$ and $2 \mathrm{r}$
Current Electricity

152536 The voltage $V$ and current $I$ graph for a conductor at two different temperatures $T_{1}$ and $T_{2}$ and shown in the figure. The relation between $T_{1}$ and $T_{2}$ is :

1 $\mathrm{T}_{1}>\mathrm{T}_{2}$
2 $\mathrm{T}_{1}\lt\mathrm{T}_{2}$
3 $\mathrm{T}_{1}=\mathrm{T}_{2}$
4 $\mathrm{T}_{1}=\frac{1}{\mathrm{~T}_{2}}$
Current Electricity

152537 A battery of emf $E$ has an internal resistance $r$. $A$ variable resistance $R$ is connected to the terminals of the battery. A current $i$ is drawn from the battery. $V$ is the terminal potential difference. If $R$ alone is gradually reduced to zero, which of the following best describes $i$ and $V$ ?

1 $\mathrm{i}$ approaches zero, $\mathrm{V}$ approaches $\mathrm{E}$
2 i approaches $\frac{\mathrm{E}}{\mathrm{r}}$, V approaches zero
3 i approaches $\frac{E}{r}$, V approaches $E$
4 i approaches infinity, $V$ approaches $\mathrm{E}$
Current Electricity

152538 Two cells of emf $E_{1}$ and $E_{2}$ are joined in opposition (such that $E_{1}>E_{2}$ ). If $r_{1}$ and $r_{2}$ be the internal resistances and $R$ be the external resistance, then the terminal potential difference is :

1 $\frac{E_{1}-E_{2}}{r_{1}+r_{2}} \times R$
2 $\frac{E_{1}+E_{2}}{r_{1}+r_{2}} \times R$
3 $\frac{E_{1}-E_{2}}{r_{1}+r_{2}+R} \times R$
4 $\frac{\mathrm{E}_{1}+\mathrm{E}_{2}}{\mathrm{r}_{1}+\mathrm{r}_{2}+\mathrm{R}} \times \mathrm{R}$
Current Electricity

152539 Four identical cells of emf $E$ and internal resistance $r$ are to be connected in series. Suppose, if one of the cell is connected wrongly, the equivalent emf and effective internal resistance of the combination is :

1 $2 \mathrm{E}$ and $4 \mathrm{r}$
2 $4 \mathrm{E}$ and $4 \mathrm{r}$
3 $2 \mathrm{E}$ and $2 \mathrm{r}$
4 $4 \mathrm{E}$ and $2 \mathrm{r}$
Current Electricity

152536 The voltage $V$ and current $I$ graph for a conductor at two different temperatures $T_{1}$ and $T_{2}$ and shown in the figure. The relation between $T_{1}$ and $T_{2}$ is :

1 $\mathrm{T}_{1}>\mathrm{T}_{2}$
2 $\mathrm{T}_{1}\lt\mathrm{T}_{2}$
3 $\mathrm{T}_{1}=\mathrm{T}_{2}$
4 $\mathrm{T}_{1}=\frac{1}{\mathrm{~T}_{2}}$
Current Electricity

152537 A battery of emf $E$ has an internal resistance $r$. $A$ variable resistance $R$ is connected to the terminals of the battery. A current $i$ is drawn from the battery. $V$ is the terminal potential difference. If $R$ alone is gradually reduced to zero, which of the following best describes $i$ and $V$ ?

1 $\mathrm{i}$ approaches zero, $\mathrm{V}$ approaches $\mathrm{E}$
2 i approaches $\frac{\mathrm{E}}{\mathrm{r}}$, V approaches zero
3 i approaches $\frac{E}{r}$, V approaches $E$
4 i approaches infinity, $V$ approaches $\mathrm{E}$
Current Electricity

152538 Two cells of emf $E_{1}$ and $E_{2}$ are joined in opposition (such that $E_{1}>E_{2}$ ). If $r_{1}$ and $r_{2}$ be the internal resistances and $R$ be the external resistance, then the terminal potential difference is :

1 $\frac{E_{1}-E_{2}}{r_{1}+r_{2}} \times R$
2 $\frac{E_{1}+E_{2}}{r_{1}+r_{2}} \times R$
3 $\frac{E_{1}-E_{2}}{r_{1}+r_{2}+R} \times R$
4 $\frac{\mathrm{E}_{1}+\mathrm{E}_{2}}{\mathrm{r}_{1}+\mathrm{r}_{2}+\mathrm{R}} \times \mathrm{R}$
Current Electricity

152539 Four identical cells of emf $E$ and internal resistance $r$ are to be connected in series. Suppose, if one of the cell is connected wrongly, the equivalent emf and effective internal resistance of the combination is :

1 $2 \mathrm{E}$ and $4 \mathrm{r}$
2 $4 \mathrm{E}$ and $4 \mathrm{r}$
3 $2 \mathrm{E}$ and $2 \mathrm{r}$
4 $4 \mathrm{E}$ and $2 \mathrm{r}$