Two dipoles, made from charges ± q and ± Q respectively, have equal dipole moments. Give the
(i) ratio between the ‘separations’ of these two pairs of charges,
(ii) angle between the dipole axes of these two dipoles.
Two point charges ‘q1’ and ‘q2’ are placed at a distance ‘d’ apart as shown in the figure. The electric field intensity is zero at a point ‘P’ on the line joining them as shown. Write two conclusions that you can draw from this.
Two equal balls having equal positive charge ‘q’ coulombs are suspended by two insulating strings of equal length. What would be the effect on the force when a plastic sheet is inserted between the two ?
Five charges, q each are placed at the corners of a regular pentagon of side a.
(i) What will be the electric field at O if the charge from one of the corners (say A) is removed ?
(ii) What will be the electric field at O if the charge q at A is replaced by - q ?
Two charges q and –3q are placed on x-axis separated by distance d. Where a third charge 2q should be placed such that it will not experience any force ?
A small metallic sphere carrying charge +Q is located at the centre of a spherical cavity in a large uncharged metallic spherical shell. Write the charges on the inner and outer surfaces of the shell. Write the expression for the electric field at the point P1.
An electric dipole is placed in a uniform electric field with its dipole moment parallel to the field. Find
(i) the work done in turning the dipole till its dipole moment points in the direction opposite to .
(ii) the orientation of the dipole for which the torque acting on it becomes maximum.
An electric dipole of length 4 cm, when placed with its axis making an angle of 60° with a uniform electric field, experiences a torque of Nm. Calculate the potential energy of the dipole, if it has charge ± 8 nC.
Find the expression for electric field intensity in an axial position due to electric dipole.
An electric dipole is held in a uniform electric field.
(i) Show that the net force acting on it is zero.
(ii) The dipole is aligned parallel to the field. Find the work done in rotating it through the angle of 180°.
Two point charges q1 and q2 are located at points (a, 0, 0) and (0, b, 0) respectively. Find the electric field due to both these charges at the point (0, 0, c).
A particle of mass 10⁻³ kg and charge 5 mC enters into a uniform electric field of 2×10⁵ NC⁻¹, moving with a velocity of 20 ms⁻¹ in a direction opposite to that of the field. Calculate the distance it would travel before coming to rest.
(i) Derive the expression for electric field at a point on the equatorial line of an electric dipole.
(ii) Depict the orientation of the dipole in (i) stable, (ii) unstable equilibrium in a uniform electric field.
(i) Obtain the expression for the torque experienced by an electric dipole of dipole moment in a uniform electric field, .
(ii) What will happen if the field were not uniform?
Derive an expression for electric field of a dipole at a point on the equatorial plane of the dipole. How does the field vary at large distances?