Practice question · Multiple choice
Maxwell added the displacement current term to Ampère’s law, and light fell out of the equations. Why was that term the decisive addition?
Hints
- Ask what sustains a wave travelling through empty space.
- Faraday gives you one half of the cycle. What gives the other?
Show the answer
C. Because a changing electric field can then create a magnetic one
Why
Without the term, a field in a vacuum has nothing to regenerate it. With it, each field feeds the other, and the propagation speed computes to the measured speed of light from two electrostatic constants.
Practise Maxwell's Equations
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More questions on Maxwell's Equations
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