Advertisements
Advertisements
Question
Answer the following question.
What is the unit of dipole moment?
Advertisements
Solution
- Strength of a dipole is measured in terms of a quantity called the dipole moment.
- Let q be the magnitude of each charge and `2vec"l"` be the distance from the negative charge to the positive charge. Then, the product `"q"(2vec"l")` is called the dipole moment `vec"p"`.
- Dipole moment is defined as `vec"p"="q"(2vec"l")`
- A dipole moment is a vector whose magnitude is q (2l) and the direction is from the negative to the positive charge.
- The unit of dipole moment is coulomb-meter (C m) or debye (D).
APPEARS IN
RELATED QUESTIONS
An electric dipole of dipole moment`vecp` consists of point charges +q and −q separated by a distance 2a apart. Deduce the expression for the electric field `vecE` due to the dipole at a distance x from the centre of the dipole on its axial line in terms of the dipole moment `vecp`. Hence show that in the limit x>> a, `vecE->2vecp"/"(4piepsilon_0x^3)`
A system has two charges qA = 2.5 × 10−7 C and qB = −2.5 × 10−7 C located at points A: (0, 0, −15 cm) and B: (0, 0, +15 cm), respectively. What are the total charge and electric dipole moment of the system?
Depict the orientation of the dipole in (i) stable, (ii) unstable equilibrium in a uniform electric field.
(i)Obtain the expression for the torque `vecτ` experienced by an electric dipole of dipole moment `vecP` in a uniform electric field, `vecE` .
(ii) What will happen if the field were not uniform?
- Define torque acting on a dipole of dipole moment \[\vec{p}\] placed in a uniform electric field \[\vec{E}\] Express it in the vector from and point out the direction along which it acts. Express it in the vector from and point out the direction along which it acts.
- What happens if the field is non-uniform?
- What would happen if the external field
\[\vec{E}\] is increasing (i) parallel to \[\vec{p}\] and (ii) anti-parallel to \[\vec{p}\]?
Define electric dipole moment. Is it a scalar or a vector? Derive the expression for the electric field of a dipole at a point on the equatorial plane of the dipole.
An electric dipole is placed at the centre of a sphere. Mark the correct options.
(a) The flux of the electric field through the sphere is zero.
(b) The electric field is zero at every point of the sphere.
(c) The electric field is not zero anywhere on the sphere.
(d) The electric field is zero on a circle on the sphere.
Two particles A and B, of opposite charges 2.0 × 10−6 C and −2.0 × 10−6 C, are placed at a separation of 1.0 cm. Two particles A and B, of opposite charges 2.0 × 10−6 C and −2.0 × 10−6 C, are placed at a separation of 1.0 cm.
Two particles, carrying charges −q and +q and and of mass m each, are fixed at the ends of a light rod of length a to form a dipole. The rod is clamped at an end and is placed in a uniform electric field E with the axis of the dipole along the electric field. The rod is slightly tilted and then released. Neglecting gravity, find the time period of small oscillations.
In an electric dipole, at which point is the electric potential zero ?
When an electric dipole p is placed in a uniform electric field E then at what angle the value of torque will be maximum?
Electric charges q, q, - 2q are placed at the comers of an equilateral triangle ABC of side l. The magnitude of electric dipole moment of the system is ____________.
An electric dipole is placed at an angle of 30° to a non-uniform electric field. The dipole will experience ________.
The ratio of the weight of a man in a stationary lift and in a lift accelerating downwards with a uniform acceleration α is 3 : 2. The acceleration of the lift is:
In a non-uniform electric field, electric dipole experiences:-
Electric dipole consists of two charges of magnitude 0.1 µC separated by a distance of 2 cm. The dipole is in 5 an external field of 105 N/C. What maximum torque does the field exert on the dipole?
Polar molecules are the molecules ______.
Polar molecules are the molecules ______.
A dipole is placed in an electric field as shown. In which direction will it move?
Two charges –q each are fixed separated by distance 2d. A third charge q of mass m placed at the mid-point is displaced slightly by x(x << d) perpendicular to the line joining the two fixed charged as shown in figure. Show that q will perform simple harmonic oscillation of time period.
`T = [(8pi^3 ε_0 md^3)/q^2]^(1/2)`
The electric potential V as a function of distance X is shown in the figure.
The graph of the magnitude of electric field intensity E as a function of X is ______.
The electric field in a region is given by `vec"E" = 2/5"E"_0hat"i"+3/5"E"_0hat"j"` with `"E"_0 = 4.0xx10^3 "N"/"C"`. The flux of this field through a rectangular surface area 0.4 m2 parallel to the Y - Z plane is ______ Nm2C-1.
Show that intensity of electric field at a point in broadside position of an electric dipole is given by:
E = `(1/(4 pi epsilon_0)) p/((r^2 + l^2)^(3//2))`
Where the terms have their usual meaning.
Arrangement of an oxygen ion and two hydrogen ions in a water molecule is shown in the figure below.
Calculate the electric dipole moment of a water molecule. Express your answer in terms of e (charge on hydrogen ions), l and θ.
