Question

In order to be able to minimize the effects of changes occurring in the electrode impedances, it is necessary to employ a preamplifier having a high input impedance.

(a) True

(b) False

I had been asked this question in a job interview.

I want to ask this question from Sources of Noise in Low Level Measurements topic in section Recording System of Biomedical Instrumentation

Answer 1

Right option is (a) True

The best I can explain: True. In order to be able to minimize the effects of changes occurring in the electrode impedances, it is necessary to employ a preamplifier having a high input impedance. It has been found that a low value of input impedance gives rise to considerable distortion of the recordings.