Answer: Current through capacitor (changing E field).
- A Ordinary conduction current flowing through resistors
- B Current through capacitor (changing E field)
- C Current flowing through an ideal inductor coil
- D Steady DC current flowing through a simple closed loop
Correct answer: B. Current through capacitor (changing E field)
Explanation: Maxwell added displacement current (epsilon<sub>0</sub> x dE/dt) to Ampere's law to account for changing electric field in capacitor gaps.
In an electromagnetic wave, the oscillating electric field (E) and magnetic field (B) are perpendicular to each other and to the direction the wave travels - a purely transverse wave that needs no medium, unlike sound.
Concept context
Maxwell's equations, EM spectrum, properties, and applications of each band.