Find the noise figure of the circuits below SolutionFrom the

Solution

From the above figures in the first figure no noise because there is no resister so there is no low at two stages and inthe second figure also there is no noise.,

In this there is resistor is their, but this is no connecter to output so there is no noise in the output.,

In the third figure output is noisy because there is one resister is connexted in between input and output so there is a chance of introduction of noise into the output...,