Understanding Wave Impedence: When \eta < \eta_0

Thread starter Swapnil
Start date Oct 6, 2007
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Wave

AI Thread Summary

When an electromagnetic wave transitions from free space to a lossless medium with a refractive index greater than one, its wave impedance decreases due to the relationship between impedance, speed of light, and refractive index. The wave impedance in free space is defined as η₀, while in a medium, it is modified by the refractive index n, resulting in η = η₀/n. This reduction in impedance can be intuitively understood as the wave encountering a medium that slows it down, leading to a higher density of energy in the medium compared to free space. Consequently, the wave's ability to propagate is altered, resulting in a smaller impedance value. Understanding this concept is crucial for analyzing wave behavior in different media.

Oct 6, 2007

Swapnil

When a em-wave goes from free space to a lossless medium with a n > 1, why is it that the wave impedence \eta becomes smaller i.e. \eta = \frac{\eta_0} { n}. I know why from the math but I how to get to this result just by some intuitive reasoning?

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Oct 13, 2007

Swapnil

Anyone?

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