An electric dipole of dipole moment P → is placed in a uniform electric field E → with its axis inclined to the field. Write an expression for the torque t → experienced by the dipole in vector form. Show diagrammatically how the dipole should be kept in the electric field so that torque acting on it is (i) maximum

We have τ = PE sin θ For τ → τ man m , sin θ = max m = 1 = sin 90 ° ⇒ θ = 90 ° and τ max = PE i . e . , P → and E → Should be perpendicular to each- other means when dipole is arranged as perpendicular to the electric field.

An electric dipole of dipole moment P → is placed in a uniform electric field E → with its axis inclined to the field. Write an expression for the torque t → experienced by the dipole in vector form. Show diagrammatically how the dipole should be kept in the electric field so that torque acting on it is (i) maximum

We have τ = PE sin θ For τ → τ man m , sin θ = max m = 1 = sin 90 ° ⇒ θ = 90 ° and τ max = PE i . e . , P → and E → Should be perpendicular to each- other means when dipole is arranged as perpendicular to the electric field.

An electric dipole of dipole moment p → is placed in a uniform electric field E → with its axis inclined to the field. Write an expression for the torque τ → experienced by the dipole in vector form. Show diagrammatically how the dipole should be kept in the electric field so that torque acting on it is zero.

The torque acting on the electric dipole: τ = p → × E → = p E sin θ For, τ → τ min m , sin θ = min m = 0 = sin 0 ° ⇒ τ min m = 0 , θ = 0 ° or 180 ° i . e . , P → and E → should be parallel or antiparallel to electric field

What is the force between two small charged spheres carrying charges of 2 × 10 - 7 C and 3 × 10 - 7 C placed 30 cm apart in air?

Given, q 1 = 2 × 10 - 7 C , q 2 = 3 × 10 - 7 C , r = 30 cm = 30 × 10 - 2 m Since both charges have the same nature So, Electrostatic repulsive force = F = 1 4 π ε 0 × q 1 q 2 r 2 = 9 × 10 9 × 2 × 10 - 7 × 3 × 10 - 7 30 × 10 - 2 2 = 9 × 6 × 10 - 5 900 × 10 - 4 N = 6 × 10 - 3 N The charges are of same nature. Hence, force between them will be repulsive.

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NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 1 - Electric Charges and Fields>QUESTIONS>Q 9

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An electric dipole of dipole moment $\vec{P}$ is placed in a uniform electric field $\vec{E}$ with its axis inclined to the field. Write an expression for the torque $\vec{t}$ experienced by the dipole in vector form. Show diagrammatically how the dipole should be kept in the electric field so that torque acting on it is (i) maximum

Important Questions on Electric Charges and Fields

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NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 1 - Electric Charges and Fields>QUESTIONS>Q 9

An electric dipole of dipole moment $\vec{p}$ is placed in a uniform electric field $\vec{E}$ with its axis inclined to the field. Write an expression for the torque $\overset{}{\vec{τ}}$ experienced by the dipole in vector form. Show diagrammatically how the dipole should be kept in the electric field so that torque acting on it is zero.

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NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 1 - Electric Charges and Fields>QUESTIONS>Q 1

What is meant by electric dipole and its dipole moment? Obtain an expression for an electric field due to an electric dipole at a point on the perpendicular bisector of the dipole.

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NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 1 - Electric Charges and Fields>QUESTIONS>Q 2

Electric dipole moment is vector or scalar, if it is vector? Show its direction and obtain an expression for an electric field due to an electric dipole at a point on the axis of the electric dipole.

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NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 1 - Electric Charges and Fields>QUESTIONS>Q 3

Define dipole moment of an electric dipole. Show mathematically that the electric field intensity due to a short dipole at a distance r along its axis is twice the intensity at the same distance along the equatorial axis.

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NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 1 - Electric Charges and Fields>QUESTIONS>Q 1

What is the force between two small charged spheres carrying charges of