Question

In a common emitter amplifier circuit using an n-p-n transistor, the phase difference between the input and the output voltages will be :

• A. ${180}^o$
• B. ${45}^o$
• C. ${90}^o$
• D. ${135}^o$

Answer 1

Answer: (A)

${180}^o$

Input voltage must be forward biased output voltage must be reversed biased.

So $V$ input must be out of phase of $V$ output.

So, phase angle between them is ${180}^o$.