Question

In a common emitter transistor amplifier, the output voltage and input voltage have a phase difference of

• A. $0^c$
• B. $\frac{\pi^c}{2}$
• C. $\frac{3\pi^\circ}{4}$
• D. $\pi^c$

Hint:

Common emitter amplifier gives phase reversal: \[ 180^\circ \text{ or } \pi \text{ rad} \]

Answer 1

The Correct Option is D

Concept:
In a common emitter amplifier, the output signal is inverted relative to the input. So the output voltage is \(180^\circ\) out of phase with the input voltage. ip

Step 1: Recall the standard phase relation.
For common emitter configuration: \[ \text{phase difference} = 180^\circ \] \[ 180^\circ = \pi \text{ radians} \] ip Hence, the correct answer is:
\[ \boxed{(D)\ \pi} \]