Question: An output voltage Vout in an audio circuit is a function of an input voltage Vin and gains N and K supplied, respectively, by a transformer and an amplifier via the relationship
Vout = VinN K.
Many such circuits are to be built and used in circumstances where Vin may be somewhat variable.
(a) Considering manufacturing variability in N and K and variation in Vout attributable to environmental factors, how would you predict the mean of Vout without testing any of these complete circuits? How would you predict the amount of variability to be seen in Vout without testing any of these complete circuits?
(b) What assumption might you add to your answers to (a) in order to predict the fraction of output voltages from these circuits that will fall in the range 99 V to 100 V?
(c) Why might it be "not so smart" to rely entirely on calculations like those alluded to in (a) and (b) to the complete exclusion of product testing?