Physics-CEM (BA/BSC 2nd)

UNIT-I

Current and current density, equation of continuity. Microscopic form of Ohm’s Law (J = σE) and conductivity. Failure of Ohm’s Law. Invariance of charge. E in different frames of reference. Field of a point charge moving with constant velocity. Force between parallel currents. Behaviour of various substances in magnetic field. Definition of M and H and their relation to free and bound currents. Permeability and susceptibility and their interrelationship. B-H curve and energy loss in hysteresis, Langevin theory of diamagnetism.

UNIT-II

Lorentz’s force. Definition of B. Biot Savart’s Law and its application to long straight wire, circular current loop and solenoid. Ampere’s Circuital law and its application. Divergence and curl of B. Hall effect, expression and co-efficient. Vector potential, Definition and derivation, current density— definition, its use in calculation of change in magnetic field at a current sheet. Energy stored in magnetic field, Faraday’s Law of EM induction, Displacement current, Mutual inductance and reciprocity theorem. Self inductance for solenoid.