0 votes
in Electromagnetic induction and alternating currents by (31 points)
reopened by
A long  straight wire of length l, radius of cross section r has resistance R. If it carries a current I ,what is the poynting vector on its surface?

Please log in or register to answer this question.

1 Answer

+1 vote
by (46.2k points)

Electric field in wire,

\(E=\frac{V}{L}=\frac{IR}{L}\) (V=IR, ohm's Law)


\(H=\frac{I}{2\pi a}\) (current distributed along surface of wire)

\(S=EH=\frac{I^2R}{2\pi aL}\)

by (31 points)
Plz explain what is H. Actually I understood only that first step. Rest l didn't understand.Can u plz explain ?

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.