Title SP-4_Ch-21_Electromagnetic Induction.pdf ✅

Aakash Educational Services Limited - Regd. Office : Aakash Tower, 8, Pusa Road, New Delhi-110005 Ph. 011-47623456 Chapter Contents Chapter 21 Electromagnetic Induction Introduction Magnetic Flux Faraday’s Law of Induction Motional Electromotive Force Induced Electric Field Energy Consideration : A Quantitative Study Eddy Current Self-Inductance Self Inductances of Solenoid Mutual Inductance L-R Circuit AC Generator D.C Motor Introduction Scientist Oersted demonstrated by his experiments that electric currents can produce (induce) magnetic field in space around it. The reverse of results of Oersted’s experiments, was proved by the experimental demonstration of Faraday. The conclusion of these experiments was the electric current is generated by varying magnetic field. In this chapter, we will study the experiments of electromagnetic induction and their applications. MAGNETIC FLUX It is proportional to the number of magnetic lines passing through a surface. Mathematically . cos    B B A BA ...(i) Where B is the magnetic flux through a plane surface of area A placed in a uniform magnetic field B.  is the angle between and . B A Equation (i) can be extended to curved surfaces and non-uniform fields. B A  If the magnetic field has different magnitudes and directions at various parts of a surface as shown in figure, then the magnetic flux through the surface is given by