Answer: Switch (ON state).
- A Amplifier
- B Switch (ON state)
- C Oscillator
- D Rectifier
Correct answer: B. Switch (ON state)
Explanation: Saturation: both junctions forward biased. Maximum current flows. Used as closed switch (ON state). Cut-off (both reverse): open switch (OFF state).
Conductors have overlapping bands, semiconductors have a small energy gap that can be bridged by heat or doping, and insulators have a large gap that blocks conduction.
Concept context
Band theory, p-n junction, diodes, transistors, logic gates, and integrated circuits.