A potentiometer wire AB of length L and resistance 12r is connected to a cell D with emf ε and internal resistance 3r. Find length AJ wherein the galvanometer as shown in image shows no deflection.

Potential gradient can be expressed as the potential difference per unit length of wire.

Therefore, the potential gradient = (ε/12r + r) × (12r/L)]

= (ε/13r) × (12r/L)

= 12ε/13L

⇒ (12ε/13L )x = ε/2

⇒ x = $\frac{13L}{24}$

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A potentiometer wire AB of length L and resistance 12r is connected to a cell D with emf e and internal resistance 3r. Find length AJ wherein the galvanometer as shown in image shows no deflection.

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A student sets up the circuit as shown in the figure to find the value of unknown resistance X and records a set of readings of the voltmeter and the ammeter by using the rheostat.

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

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A potentiometer wire AB of length L and resistance 12r is connected to a cell D with emf e and internal resistance 3r. Find length AJ wherein the galvanometer as shown in image shows no deflection.

Related Questions

CBSE CLASS XII Related Questions

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3.A student sets up the circuit as shown in the figure to find the value of unknown resistance X and records a set of readings of the voltmeter and the ammeter by using the rheostat.

4.Consider the nuclear reaction \( X \to Y + Z \). Let \( M_x \), \( M_y \), and \( M_z \) be the masses of the three nuclei X, Y, and Z respectively. Then which of the following relations hold true?

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

6. The resistance of a metal wire at \( 20^\circ \text{C} \) is \( 1.05 \, \Omega \) and at \( 100^\circ \text{C} \) is \( 1.38 \, \Omega \). Determine the temperature coefficient of resistivity of this metal.

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Comments

SUBSCRIBE TO OUR NEWS LETTER

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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 ?

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