Questions - Semiconductors

Question file 11


  1. The basic semiconductor amplifying device is a:                         STUDY NOTES 
    1. diode
    2. transistor                                                                 QUESTIONS WITHOUT ANSWERS 
    3. pn-junction
    4. silicon gate
    ========= Answer is b =========
  2. Zener diodes are normally used as:
    1. RF detectors
    2. AF detectors
    3. current regulators
    4. voltage regulators
    ========= Answer is d =========
  3. The voltage drop across a germanium signal diode when conducting is about:
    1. 0.3V
    2. 0.6V
    3. 0.7V
    4. 1.3V
    ========= Answer is a =========
  4. A bipolar transistor has three terminals named:
    1. base, emitter and drain
    2. collector, base and source
    3. emitter, base and collector
    4. drain, source and gate
    ========= Answer is c =========
  5. The three leads from a PNP transistor are named the:
    1. collector, source, drain
    2. gate, source, drain
    3. drain, base, source
    4. collector, emitter, base
    ========= Answer is d =========
  6. A low-level signal is applied to a transistor circuit input and a higher-level signal is present at the output. This effect is known as:
    1. amplification
    2. detection
    3. modulation
    4. rectification
    ========= Answer is a =========
  7. The type of rectifier diode in almost exclusive use in power supplies is:
    1. lithium
    2. germanium
    3. silicon
    4. copper-oxide
    ========= Answer is c =========
  8. One important application for diodes is recovering information from transmitted signals. This is referred to as:
    1. biasing
    2. rejuvenation
    3. ionisation
    4. demodulation
    ========= Answer is d =========
  9. In a forward biased pn junction, the electrons:
    1. flow from p to n
    2. flow from n to p
    3. remain in the n region
    4. remain in the p region
    ========= Answer is b =========
  10. The following material is considered to be a semiconductor:
    1. copper
    2. sulphur
    3. silicon
    4. tantalum
    ========= Answer is c =========
  11. A varactor diode acts like a variable:
    1. resistance
    2. voltage regulator
    3. capacitance
    4. inductance
    ========= Answer is c =========
  12. A semiconductor is said to be doped when small quantities of the following are added:
    1. electrons
    2. protons
    3. ions
    4. impurities
    ========= Answer is d =========
  13. The connections to a semiconductor diode are known as:
    1. cathode and drain
    2. anode and cathode
    3. gate and source
    4. collector and base
    ========= Answer is b =========
  14. Bipolar transistors usually have:
    1. 4 connecting leads
    2. 3 connecting leads
    3. 2 connecting leads
    4. 1 connecting lead
    ========= Answer is b =========
  15. A semiconductor is described as a "general purpose audio NPN device". This is a:
    1. triode
    2. silicon diode
    3. bipolar transistor
    4. field effect transistor
    ========= Answer is c =========
  16. Two basic types of bipolar transistors are:
    1. p-channel and n-channel types
    2. NPN and PNP types
    3. diode and triode types
    4. varicap and zener types
    ========= Answer is b =========
  17. A transistor can be destroyed in a circuit by:
    1. excessive light
    2. excessive heat
    3. saturation
    4. cut-off
    ========= Answer is b =========
  18. To bias a transistor to cut-off, the base must be:
    1. at the collector potential
    2. at the emitter potential
    3. mid-way between collector and emitter potentials
    4. mid-way between the collector and the supply potentials
    ========= Answer is b =========
  19. Two basic types of field effect transistors are:
    1. n-channel and p-channel
    2. NPN and PNP
    3. germanium and silicon
    4. inductive and capacitive
    ========= Answer is a =========
  20. A semiconductor with leads labelled gate, drain and source, is best described as a:
    1. bipolar transistor
    2. silicon diode
    3. gated transistor
    4. field-effect transistor
    ========= Answer is d =========