1. Edward C. Jordan Memorial Offering of the First Course under the Indo-US Inter-University Collaborative Initiative in Higher Education and Research: Electromagnetics for Electrical and Computer Engineering by Nannapaneni Narayana Rao Edward C. Jordan Professor of Electrical and Computer Engineering University of Illinois at Urbana-Champaign Urbana, Illinois, USA Amrita Viswa Vidya Peetham, Coimbatore July 10 – August 11, 2006

2. 2.6 The Law of Conservation of Charge

3. 2.6-2 Law of Conservation of Charge Current due to flow of charges emanating from a closed surface S = Time rate of decrease of charge enclosed by S. (t)(t)

4. 2.6-3 Summarizing, we have the following: Maxwell’s Equations (1) (2) (3) (4)

5. 2.6-4 Law of Conservation of Charge (4) is, however, not independent of (1), whereas (3) follows from (2) with the aid of (5). (5)

6. 2.6-5 (Ampére’s Circuital Law) (Gauss’ Law for the electric field and symmetry considerations) Example:

7. 2.6-6 (Law of Conservation of charge)