Two charges q₁ and q₂ are placed 30 cm apart, as shown in the figure. A third charge q₃ is moved along the arc of a circle of radius 40 cm from C to D.

The change in the potential energy of the system is $${{{q_3}} \over {4\pi {\varepsilon _0}}}$$ where k is

As per the diagram a point charge +q is placed at the origin O. Work done in taking another point charge $$-$$Q from the point A [coordinates (0, $$a$$)] to another point B

A bullet of mass 2 g is having a charge of 2 $$\mu $$C. Through what potential difference must it be accelerated, starting from rst, to acquire a speed of 10 m/s ?

An electric dipole has the magnitude of its charge as q and its dipole moment is p. It is placed in a uniform electric field E. If its dipole moment is along the direction of the field, the force on it and its potential energy are respectively