Phase Inversion generally occurs for which of the following cases ?

Phase Inversion generally occurs for which of the following cases ?

a. Inversion of AC output voltage w.r.t input voltage by 180 degree in phase
b. Inversion of DC output voltage w.r.t AC input voltage by zero degree
c. Inversion of AC output voltage w.r.t input voltage by 180 degree out of phase.
d. None of the above

Correct Answer : c. Inversion of AC output voltage w.r.t input voltage by 180 degree out of phase.

Explanation :

Collector Current & voltage swings over the 'Q' value due to fluctuation in base current. Thus, AC output voltage gets inverted by 180 degree (out of phase) corresponding to input voltage.