##  [Johnson-Nyquist Noise](/johnson-nyquist-noise) 

  ##  [Johnson-Nyquist Noise](https://engineering.quantumdictionary.io/johnson-nyquist-noise-0) 

  

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**Engineering & Applied Technologies Dictionary**

 







 

 

 

 



 

 

 

 

Definition

Random electrical voltage or current fluctuations generated by the thermal agitation of charge carriers in a resistive element at thermal equilibrium; for a linear resistor at temperature T the equilibrium one‑sided voltage power spectral density is S_v(f) = 4 k_B T R (classically frequency‑independent, with quantum corrections when hf ≳ k_B T).