Question

On increasing the distance between the plates of a variable capacitor, the displacement- capacitance characteristics changes _______

(a) proportionally

(b) linearly

(c) exceptionally

(d) hyperbolically

I have been asked this question in an online interview.

Origin of the question is Displacement, Position and Motion Transducers in portion Physiological Transducers of Biomedical Instrumentation

Answer 1

The correct choice is (d) hyperbolically

The explanation: By moving one plate of the capacitor with respect to the other, the capacitance will vary inversely with respect to the plate separation. This will give a hyperbolic displacement capacitance characteristic. This is how variable capacitance is employed as displacement transducers.