Advertisements
Advertisements
प्रश्न
Answer the following question.
Derive an expression for the electric field at any point on the equatorial line of an electric dipole.
Advertisements
उत्तर
Electric field for points on the equator plane
The magnitude of the electric field due to two charges +q and –q is
`E_(+q) = q/(4piε_0)1/(r^2 + a^2)`
`E_(-q) = q/(4piε_0)1/(r^2 + a^2)`
`E_(+q) = E_(-q)`
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)) costheta hatp` ......(Negative sign shows that the field is opposite to `hatp`)
`E = -(2qa)/(4piε_0(r^2 + a^2)^(3/2))hatp` ...(iii)
At large distance (r >> a), this reduces to,
`E = -(2qa)/(4piε_0r^3)hatp`
`vecp = q xx 2vecahatp`
`E = -vecp/(4piε_0r^3)` ....(r >> a)
संबंधित प्रश्न
Derive the expression for the electric potential due to an electric dipole at a point on its axial line.
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.
A sample of HCI gas is placed in an electric field of 2.5 × 104 NC−1. The dipole moment of each HCI molecule is 3.4 × 10−30 Cm. Find the maximum torque that can act on a molecule.
Answer the following question.
What is the unit of dipole moment?
A conic surface is placed in a uniform electric field E as shown in the figure such that the field is perpendicular to the surface on the side AB. The base of the cone is of radius R, and the height of the cone is h. The angle of the cone is θ.
Find the magnitude of the flux that enters the cone's curved surface from the left side. Do not count the outgoing flux (θ < 45°)
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:
Polar molecules are the molecules ______.
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.
