Amplifier Characteristics and Efficiency

The video tutorial reviews the characteristics of three types of amplifiers: common emitter, common base, and common collector. It explains the input and output configurations, signal inversion, and impedance properties of each amplifier. The common emitter amplifier is noted for its high power gain, while the common base amplifier has a low current gain. The common collector amplifier is highlighted for its high input impedance and low output impedance. The video also discusses the power gain and efficiency of these amplifiers, comparing them to class A and class B amplifiers.

What is the primary reason the common emitter amplifier is named as such?

• The input is applied to the emitter.

• The collector is common to both input and output circuits.

• The emitter is common to both input and output circuits.

• The output is taken from the base.

Which characteristic is NOT associated with the common emitter amplifier?

• High power gain

• Low voltage gain

• Mid-range input impedance

• Mid-range current gain

In the common base amplifier, where is the input signal applied?

• Collector

• Load resistor

• Base

• Emitter

Which of the following is a characteristic of the common base amplifier?

• Inverted output signal

• Low output impedance

• High current gain

• Low input impedance

What is a key feature of the common collector amplifier?

• High voltage gain

• Low input impedance

• Inverted output signal

• High input impedance

Which amplifier type is known for having a low voltage gain?

• Common emitter

• Class B

• Common base

• Common collector

What is the maximum theoretical efficiency of a class A amplifier?

• 78.5%

• 100%

• 25%

• 50%

Which amplifier type is most suitable for achieving high power gain?

• Common emitter

• Common collector

• Common base

• Class B

What is the relationship between voltage gain and current gain in determining power gain?

• Power gain is the difference between voltage and current gain.

• Power gain is the ratio of voltage to current gain.

• Power gain is the sum of voltage and current gain.

• Power gain is the product of voltage and current gain.

Which class of amplifier uses two transistors and has a higher efficiency than class A?

• Class D

• Class B

• Class C

• Class E