Potentiometer Principle - Comparing the Emf of Two Cells

Write down five disadvantage of the potentiometer.

What kind of precautions shpuld we take while using potentiometer?

A potentiometer is an accurate and versatile device to make electrical measurements of $\mathrm{emf}$ because the methods involves:

Potentiometer is most sensitive than voltmeter because

The $\mathrm{emf} \mathrm{E}=20\mathrm{V}, \mathrm{r}=2\mathrm{\Omega }, \mathrm{E}\text{'}=4\mathrm{R}, \mathrm{R}=3\mathrm{\Omega }, \mathrm{AB}=100\mathrm{cm}$ and resistance per unit length of potentiometer wire $\mathrm{AB}$ is $2 \raisebox{1ex}{$\mathrm{\Omega }$}\!\left/ \!\raisebox{-1ex}{$\mathrm{m}$}\right.$. Find the null point length $\mathrm{AJ}$ in the given below circuit diagram of a potentiometer.

If the radius of the potentiometer wire is doubled then effect on null point-

The sensitivity of a potentiometer can be increased by_____________________?

Standardisation of potentiometer is done in order that they become-

The length of a wire of potentiometer is $100 \mathrm{cm}$ and the $\mathrm{emf}$ of its standard cell is $\mathrm{E} \mathrm{volt}$. It is employed to measure the $\mathrm{emf}$ of a battery whose internal resistance is $0.5\mathrm{\Omega }$. If the balance point is obtained at $\mathrm{l}=30\mathrm{cm}$ from the $+\mathrm{ve}$ and the $\mathrm{emf}$ of the battery is

Pick out the application of potentiometer from the following.

The balancing length of a potentiometer is at $120 \mathrm{cm}$. On shunting the cell with a resistance of $4\mathrm{\Omega }$, the balancing point shifts to a length of $60 \mathrm{cm}$. Then, find the internal resistance of the cell.

A potentiometer wire of length $20 \mathrm{cm}$ has a resistance of $50\mathrm{\Omega }$. It is connected in series with a resistance box and a $5\mathrm{V}$ storage cell. If the potential gradient along the wire is $0.5 \mathrm{m}\raisebox{1ex}{$\mathrm{V}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{cm}$}\right.$. What is the resistance unplugged in the box?

A potentiometer wire of length $100 \mathrm{cm}$ has a resistance of $30\mathrm{\Omega }$. It is connected in series with a resistance of $20\mathrm{\Omega }$ and accumulator of $\mathrm{emf} 8\mathrm{V}$ having negligible internal resistance. A source of $1.2 \mathrm{V}$ is balanced against a length of the potentiometer wire, what is the value of $\mathrm{L}$?

A potentiometer is basically a Calibrating instrument

Why potentiometer is used in calibration of ammeter ?

A cell of $2\mathrm{V},\mathrm{ }1\mathrm{\Omega }$ is balanced at $1.9\mathrm{ }\mathrm{m}$. Then what is balanced length for ideal cell of $2\mathrm{V}$ ?

 In the following figure, the $p.d.$ between the points $M$ and $N$ is balanced against $50 \mathrm{cm}$ length of potentiometer wire of total length $100 \text{cm}$. In order to balance the potential difference between the points $N$ and $C$ the jockey to be pressed on potentiometer wire at a distance of $\left(\text{in cm}\right)$:

The potential gradient of potentiometer is $0.2 \mathrm{volt} {\mathrm{m}}^{-1}$. $A$ current of $0.1 \mathrm{amp}$ is flowing through $a$ coil of $2 \mathrm{Ohm}$ resistance. The balancing length in meters for the$\mathrm{p}.\mathrm{d}.$ at the ends of this coil will be

The length of a wire of a potentiometer is $100 \mathrm{cm},$ and the emf of its standard cell is $E \mathrm{volt}$. It is employed to measure the emf of a battery whose internal resistance is $0.5 \mathrm{Ohm}$. If the balance point is

The potential gradient of a potentiometer wire is defined as