Justifying Ampere's Law and Faradays Law with an experiment

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SUMMARY

This discussion centers on the comparative ease of demonstrating Faraday's Law versus Ampere's Law through experimental design. Faraday's Law, which states that a changing magnetic field induces an electric field, can be easily illustrated by moving a magnet near a conductor, resulting in observable current in a coil. In contrast, demonstrating Ampere's Law, which involves the relationship between electric fields and magnetic fields, is more complex as it requires creating a changing electric field without the influence of current, a task that necessitates advanced tools for controlling electromagnetic phenomena.

PREREQUISITES
  • Understanding of Faraday's Law and its implications in electromagnetism
  • Familiarity with Ampere's Law and its mathematical representation
  • Basic knowledge of electromagnetic fields and their interactions
  • Experience with experimental physics techniques for measuring electric and magnetic fields
NEXT STEPS
  • Research experimental setups for demonstrating Faraday's Law using magnets and coils
  • Explore advanced techniques for generating and measuring changing electric fields
  • Study the mathematical derivations of Ampere's Law and its applications in real-world scenarios
  • Investigate tools and technologies for controlling electromagnetic fields, such as oscilloscopes and signal generators
USEFUL FOR

Physics students, educators, and experimental physicists interested in deepening their understanding of electromagnetic theory and practical applications of Faraday's and Ampere's Laws.

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Homework Statement


Given Ampere's Law and Faraday's Law (in differential or integral form fwiw) explain why it is easier to design an experiment to show that a changing magnetic field creates an electric field than it is to show a changing electric field creates a magnetic field. Justify your answer with numbers.

Homework Equations


##\nabla x \vec{B} = \mu_0\vec{J} + \mu_0\epsilon_0\frac{d\vec{E}}{dt}##
##\nabla x \vec{E} = \frac{-d\vec{B}}{dt}##

The Attempt at a Solution


So this was from an exam I just took. I beat my head against it for about 45 minutes and could only really come up with this:

For Faraday's law, it only requires that a changing magnetic field be present. This can be accomplished easily by simply moving a magnet around a conductor, since if an electric field is created, the electrons in the conductor will move, and we can see the effects of this in a coil of wire with a segment cut out. As the magnet moves sparks of current should be visible at that cut out.

For Ampere's Law however it is hard to create a changing electric field independent of current (where ##\vec{J} = \vec{0}##). One would need to create a changing electric field that propagates through free space and measure the magnetic effects on objects as a result, which would have been challenging without tools that can properly control photons.

I honestly just didn't know how to describe the difficulties of Ampere's Law better than this. And I didn't have time to think of any numerical justifications for my arguments since the other 3 problems also took about 45 minutes a piece. How would you have gone about answering this differently?
 
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Hard to change the electric field without moving charges about yes.
 

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