Three identical cells of 4 V and internal resistance r are connected in series?

Internal resistance can be defined as the opposition to the current’s flow supplied by the cells and batteries themselves, resulting in heat production.

Step 1: Given Data

As per the question,

Total EMF = 4 $\times$ 3 = 12 V
Total Resistance = 6 + 3r
Current = 2 A

Step 2: Calculation of Given Data

The question can be solved using Ohm’s Law. Therefore,

2 = ${{12} \over (6+3r)}$

⇒ 2 (6+3r) =12
⇒ 12 + 6r = 12
⇒ 6r = 12 – 12 = 0
⇒ r = ${{0} \over 6}$ = 0

Hence, the internal resistance of each cell is 0.

Read More: Ohm’s Law and its Limitations

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Three identical cells of 4 V and internal resistance r, are connected in series to a 6 resistor 2 A current in circuit. What is the internal resistance of each cell?

Step 1: Given Data

Step 2: Calculation of Given Data

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4.
With the help of a labelled diagram, explain the principle, construction and working of an a.c. generator.

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Three identical cells of 4 V and internal resistance r, are connected in series to a 6 resistor 2 A current in circuit. What is the internal resistance of each cell?

Step 1: Given Data

Step 2: Calculation of Given Data

CBSE CLASS XII Related Questions

1.Two metal spheres of radii $r_1$ and $r_2$ ($> r_1$) having charges $q_1$ and $q_2$ respectively kept in air, are brought in contact. Which of the following statements is not correct ?

4.With the help of a labelled diagram, explain the principle, construction and working of an a.c. generator.

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

1.
Two metal spheres of radii $r_1$ and $r_2$ ($> r_1$) having charges $q_1$ and $q_2$ respectively kept in air, are brought in contact. Which of the following statements is not correct ?

4.
With the help of a labelled diagram, explain the principle, construction and working of an a.c. generator.