Vacuum Impedance: Physical Origin Explained

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Vacuum impedance is approximately 377 ohms, derived from the plane wave solutions of Maxwell's equations. This impedance represents the ratio of the electric field (E) to the magnetic field (H) in free space. It is calculated as the square root of the ratio of magnetic permittivity (μ) to electric permittivity (ε). The characteristic impedance of free space is specifically noted to be 376.6 ohms. Understanding this concept is crucial for applications in electromagnetism and wave propagation.
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The vacuum impedance,as our professor writes in blackboard, equals 377 ohm
What is the physical origin of this impedance?
 
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This value arises from the plane wave solution of Maxwell's equations.
The ratio of E/H in a plane wave in free space is equal to the square
root of the ratio of the magnetic permittivity (mu) to the electric permittivity (epsilon).
This value has the dimensions of ohms and is called the characteristic
impedance of free space and has the value of 376.6 ohms.
 

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