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Posted: **Fri May 20, 2022 8:01 pm**

: Consider The Following Common Scenario Where An Unused Installed Coaxial Cable In A Fridge Is Closed Off At The Top Dur 1 (45.17 KiB) Viewed 36 times

: Consider The Following Common Scenario Where An Unused Installed Coaxial Cable In A Fridge Is Closed Off At The Top Dur 2 (9.04 KiB) Viewed 36 times

Consider the following common scenario, where an unused installed coaxial cable in a fridge is closed off at the top during a cooldown where it is not required: 300K 50K 20 4K The Lat the top indicates that the line has been terminated with a matched 50 Ohm impedance at the room temperature coaxial input port. The 20 indicates that a 20 dB attenuator has been installed at (and thermally clamped to) the 4K fridge stage. Assuming room temperature is at 300 K and the nominal "4K" plate is currently running at 3.81 K, follow the instruction in the next question. (This question is a placeholder only.)

Calculate the total noise power (per unit bandwidth) seen from below the 20 dB attenuator. Show your working. Partial marks will be awarded for this question.]