Advertisements
Advertisements
प्रश्न
Draw a labelled circuit diagram of a potentiometer to measure the internal resistance ‘r’ of a cell. Write the working formula (derivation is not required).
Advertisements
उत्तर

The internal resistance can be found using the formula
`r = R(l_1/l_2- 1)`
where R is the resistance of the resistance box connected to the cell through key K2 and l1 and l2 are the balancing lengths corresponding to the cases when key K2 is open and is closed respectively .
APPEARS IN
संबंधित प्रश्न
On what factors does the potential gradient of the wire depend?
Why is a potentiometer preferred over a voltmeter for measuring emf?
When the null point is obtained in the potentiometer, the current is drawn from the ______
What is the SI unit of potential gradient?
To determine the internal resistance of a cell by using potentiometer, the null point is at 1 m when cell is shunted by 3 Ω resistance and at a length 1.5 m when cell is shunted by 6 Ω resistance. The internal resistance of the cell is ______.
In the potentiometer experiment, the balancing length with a cell E1 of unknown e.m.f. is 'ℓ1' cm. By shunting the cell with resistance R Ω, the balancing length becomes `ℓ_1/2` cm, the internal resistance (r) of a cell is ______
A potentiometer is an accurate and versatile device to make electrical measurements of E.M.F. because the method involves ______.
What is the current I in the circuit as show in fig.

Two identical thin metal plates has charge q1 and q2 respectively such that q1 > q2. The plates were brought close to each other to form a parallel plate capacitor of capacitance C. The potential difference between them is ______.
What is the internal resistance of the cell?
