Johnson and Shot Noise at 20*C with 9V Battery and 100Kohm Resistor

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SUMMARY

The discussion focuses on calculating Johnson and shot noise for a 100Kohm resistor connected to a 9V battery at a temperature of 20°C with a measurement bandwidth of 10KHz. Johnson noise is determined using the formula Vrms = √(4KTRB), where K is the Boltzmann constant, T is the temperature in Kelvin, R is resistance, and B is bandwidth. The shot noise is calculated using Irms = √(2eIB), indicating that shot noise is independent of temperature. The discussion also raises the question of at what temperature the contributions of Johnson and shot noise become equal, assuming the resistor's resistance remains constant.

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A battery of emf 9V, and negligible internal resistance, has a 100Kohm resistor connected across its terminals. What are the values of johnson and shot noise at a temperature of 20*C if the measurement bandwidth is 10KHz?

At what temperature would the johnson and shot noise contributions to the noise voltage across the resistor become equal? [ assume that the resistor is independent of temperature]

Will put up my attempts later! any help would be good.
 
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Ok can find johnson noise by Vrms = [4KTRB]^1/2 where k is Boltzmann constant, T is temperature R is resistance and B is bandwidth.

Show noise found by Irms = [2eIB]^1/2 so I am presuming shot noise is independent of temperature?
 
Solved.
 

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