a) What is the magnitude of a point electric charge chosen so that the electric field because of it at a point 50 cm away has magnitude 2.0 NC¯¹ ?
(b) Get a mathematical expression for the magnetic field strength at the center of a circular coil carrying electric current?
(c) Illustrate the electronic configuration in the atomic structures of 'Ge' and 'Si' atoms. How can these be made 'P-type' and 'N- type' semi - conductors?