An electric dipole is kept  perpendicular to a ‘non-uniform’ electric field. What will be the motion of the dipole?

Sketch the electric lines of force due to point-charges: q < 0

Sketch the electric lines of force due to point-charges: q > 0.

Figure shows electric lines of force due to two point-charges ${\mathrm{q}}_1$ and ${\mathrm{q}}_2$ placed at points A and B respectively. Write the nature of charges.

Consider the situation shown in the figure. What are the signs of ${\mathrm{q}}_1$ and ${\mathrm{q}}_2$?

State and explain: the principle of superposition as applied to electrostatic forces on a charge due to a number of charges.