Sign In Sign Up Ask an AI advisor
princesincer9256
princesincer9256
15.10.2019 • 
Engineering

An experimentalist wishes to measure the resistance rs of a sample located down in a cryostat. two wires, each with resistance r = 10ω, carry an ac current i = 1.0 ma down into the cryostat, through the sample, and back up to ground. the voltage across the sample is measured with a differential amplifier. the actual sample resistance is rs = 0.10ω. 1.0ma r 10ω rs 0.10ω r 10ω − + vout (a) what is the differential voltage at the amplifier inputs? (b) what is the common-mode voltage? (c) suppose the amplifier is similar to the one you will build in lab, with gdiff = 10 and gcm = 0.50. what is the amplitude of the ac signal at vout? (d) if the experimenter assumed that her amplifier was ideal, with gdiff = 10 but gcm = 0, what would she report for the value of rs? (e) what is the minimum cmrr (= gdiff/gcm) her amplifier would need in order to measure rs to an accuracy of 1%?

Solved
Show answers

Ask an AI advisor a question

I want advice