Physics > Current Electricity > 9.0 Potentiometer
Current Electricity
1.0 Introduction
2.0 Conduction of current in a metal
3.0 Ohm's law
3.1 Temperature dependence of resistance
3.2 Resistivities of different materials
3.3 Limitations of ohm's law
4.0 Combination of Resistors
5.0 Electromotive force $\left( \xi \right)$
6.0 Heating effect of current
7.0 Wheatstone bridge
8.0 Metre Bridge Or Slide wire bridge
9.0 Potentiometer
9.1 Comparison of emfs of two primary cells.
9.2 Determination of Internal resistance of a cell using potentiometer
10.0 Electrical devices
9.1 Comparison of emfs of two primary cells.
3.2 Resistivities of different materials
3.3 Limitations of ohm's law
9.2 Determination of Internal resistance of a cell using potentiometer
Let ${l_1}$ and ${l_2}$ be the balancing length with cell ${\xi _1}$ and ${\xi _2}$ respectively.
Then, $$\begin{equation} \begin{aligned} \Rightarrow {\xi _1} = k{l_1} \\ \Rightarrow {\xi _2} = k{l_2} \\\end{aligned} \end{equation} $$
Hence, $$\frac{{{\xi _1}}}{{{\xi _2}}} = \frac{{{l_1}}}{{{l_2}}}$$