An electric dipole with dipole moment 4 × 10–9 C m is aligned at 30°with the direction of a uniform electric field of magnitude 5 × 104 NC–1.Calculate the magnitude of the torque acting on the dipole.

Open in App

Solution

Given: The electric dipole moment of the system is 4× 10 −9 C-m, angle between electric dipole and uniform electric field is 30° and electric field is 5× 10 4 N/C.

The torque acting on the dipole is given as,

τ=pEsinθ

Where, p is the electric dipole moment of the system, E is the electric field and θ is the angle between uniform electric field and electric dipole moment.

By substituting the given values in the above equation, we get

τ=4× 10 −9 ×5× 10 4 ×sin30° =20× 10 −5 × 1 2 = 10 −4 N-m

Thus, the magnitude of the torque acting on the dipole is 10 −4 N-m.

Suggest Corrections

Similar questions

An electric dipole with dipole moment $4 \times 10^{- 9}$ C m is aligned at $30^{\circ}$ with the direction of a uniform electric field of magnitude $5 \times 10^{4} N C^{- 1}$ . Calculate the magnitude of the torque acting on the dipole.

Q. What will be the magnitude of torque on an electric dipole having dipole moment of

4 \times 10^{- 9} c m

placed in a uniform electric field of intensity of

5 \times 10^{4} N C^{- 1}

making an angle

180^{o}

with the field.

Q. If the dipole of moment

2.57 \times 10^{- 17} C . m

is placed into an electric field of magnitude

3.0 \times 10^{4} N / C

such that the fields lines are aligned at

30^{o}

with the line joining the dipole, what torque will act on the dipole?

Q. An electric dipole, consisting of two opposite charges of magnitude

2 \times 10^{- 6}

C each separated by a distance 3 cm is placed in an electric field of magnitude

2 \times 10^{5}

N/C along the direction making

90^{0}

with the field. Torque acting on the dipole is :

Q. An electric dipole is placed in an uniform electric field of magnitude

40 N/C

. The graph given below represents the magnitude of the torque on dipole versus the angle

θ

between field and dipole moment. The magnitude of dipole moment is equal to

Join BYJU'S Learning Program