Could someone explain the equation describing Thermal Noise?(adsbygoogle = window.adsbygoogle || []).push({});

The equation is given by

[tex]

\overline{\left(\delta U\right)^{2}_{kT}} = 4RkT\Delta f

[/tex]

Specifically I dont understand what the [tex]\Delta f[/tex] is. Some online resources describe [tex]\Delta f[/tex] as:

- "frequency bandwidth within which information is sought"

- "bandwidth being considered"

- "bandwidth over which noise is measured"

These descriptions are a bit vague. Could someone explain [tex]\Delta f[/tex] in more detail.

thanks.

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# Thermal Noise (Johnson–Nyquist)

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