Inductance and Capacitance per Temperature

[americanforest]

I am studying the relationship between transmission speed in a Transmission Cable and the temperature of the cable. This speed is given by (as per discussion in the Feynman lectures)

[tex]v=\frac{1}{\sqrt{LC}}[/tex] where

• [tex]L[/tex] is the inductance per unit length
• [tex]C[/tex] is the capacitance per unit length

Does anyone know how the inductance and capacitance are expected to vary with temperature? The range examined in the experiment is approximately 20-50 degrees Celsius.

 

[f95toli]

How much it will change basically depends on the properties of the dielectric (I am assuming you are referring to a coaxial cable).
The change should be very small assuming one of the more common dielectric is used, e.g. PTFE etc. I doubt creep will be much of an issue in such a small temperature range.

Also, if the range in question includes room temperature you should be able to find this data in a datasheet, they typically list data from -50 to +80 degrees C or so, at least if the cable conforms to military specs (and most coaxes do)

 

[astrokreng]

I can provide some insights on the expected behavior of inductance and capacitance with changing temperature. Both inductance and capacitance are properties of a material or component that determine its ability to store and transmit electrical energy.

In general, the inductance of a material or component is expected to increase with an increase in temperature. This is because as temperature rises, the vibrations and movements of the atoms and molecules in the material increase, leading to a higher resistance to the flow of electrons. This in turn increases the inductance of the material.

On the other hand, the capacitance of a material or component is expected to decrease with an increase in temperature. This is because at higher temperatures, the atoms and molecules in the material have more energy and are able to move more freely, reducing the ability of the material to store electrical energy.

In your experiment, the range of temperatures being examined (20-50 degrees Celsius) is relatively small and may not result in significant changes in inductance and capacitance. However, it is important to keep in mind that the exact relationship between temperature and these properties may vary depending on the specific materials and components being used. Therefore, it is important to carefully monitor and measure these properties at different temperatures to accurately understand their behavior in your experiment.