Advertisements
Advertisements
प्रश्न
Drive the expression for electric field at a point on the equatorial line of an electric dipole.
Advertisements
उत्तर
Electric Field for Points on the Equatorial Plane:

The magnitudes of the electric field due to the two charges +q and −q are given by,
`E_(+q)=q/(4piepsilon_0)1/(r^2+a^2)` .....(i)
`E_(-q)=q/(4piepsilon_0)1/(r^2-a^2)` .....(ii)
The directions of E+q and E−q are as shown in the figure. The components normal to the dipole axis cancel away. The components along the dipole axis add up.
∴ Total electric field
`E=-(E_(+q)+E_(-q))cos theta.hatp`[Negative sign shows that field is opposite to `hatp`]
`E=-(2qa)/(4piepsilon_0(r^2+a^2)^(3/2))hatp` .....(iii)
At large distances (r >> a), this reduces to
`E=-(2qa)/(4piepsilon_0(r^3))hatp` .....(iv)
`because vecp=qxxvec(2a)hatp`
`therefore E=(-vecp)/(4piepsilon_0(r^3))` (r >> a)
APPEARS IN
संबंधित प्रश्न
Find the resultant electric field due to an electric dipole of dipole moment, 2aq, (2a being the separation between the charges ±± q) at a point distant 'x' on its equator.
Define electric dipole moment.
In which orientation, a dipole placed in a uniform electric field is in (i) stable, (ii) unstable equilibrium?
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. Calculate the electric field at a point on the axis of the dipole 1.0 cm away from the centre.
Answer the following question.
What is the unit of dipole moment?
A metal sphere of radius 1 cm is given a charge of 3.14 µC. Find the electric intensity at a distance of 1 m from the centre of sphere.
`[epsilon_0 = 8.85 xx 10^-12 "F"//m]`
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 ____________.
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:-
