How does energy flow from voltage source to resistor in a simple DC circuit?

Let us consider a simple dc circuit consisting of a battery and a resistor connected by ideal wires. As we know, current starts to flow thorugh the resistor and heat is generated as a result of this current flow. We need to determine how this energy is transferred from the voltage source to the resistor. The answer, suprisingly, is that the ideal wires connecting the battery to the resistor carry no energy at all. Most of the energy flows around the ideal wires. This is because the electric field inside the wires is zero and according to the Poynting theorem, no energy can flow if the electric field is zero in any given region of space. However, a radial electric field exists outside the current carrying wires and hence energy flows parallel to the wires and gets converted to heat in the resistor. 

SH
Answered by Sree Harsha N. Physics tutor

3058 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

Describe how standing waves are formed and explain why nodes and antinodes are formed.


What are the assumptions made when calculating values regarding an Ideal Gas?


A boy (25kg) and a girl (20kg) are playing on a see-saw which is 4m long. If the boy sits 1m from the centre on the left side and the girl 2m from the centre on the other, which direction will the see-saw will rotate around its centre?


If a car is traveling at a speed of 10m/s. The driving force of 500N is required to keep the speed constant . What is the power supplied by the engine?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning