

MCQOPTIONS
Saved Bookmarks
This section includes 33 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics knowledge and support exam preparation. Choose a topic below to get started.
1. |
Which is the seven-segment display? |
A. | [A]. |
B. | [B]. |
C. | [C]. |
D. | [D]. |
Answer» B. [B]. | |
2. |
Which is the TRIAC? |
A. | [A]. |
B. | [B]. |
C. | [C]. |
D. | [D]. |
Answer» E. | |
3. |
Which is the DIAC? |
A. | [A]. |
B. | [B]. |
C. | [C]. |
D. | [D]. |
Answer» B. [B]. | |
4. |
The silicon-controlled rectifier (SCR) is a three-layer device consisting of a gate, an anode, and a cathode. |
A. | 1 |
B. | |
Answer» C. | |
5. |
A transducer does not convert energy from one form to another. |
A. | 1 |
B. | |
Answer» C. | |
6. |
SCRs are four-layer devices that are either fully conducting or not conducting. |
A. | 1 |
B. | |
Answer» B. | |
7. |
A DIAC is a bidirectional diode that has a symmetrical switching mode. |
A. | 1 |
B. | |
Answer» B. | |
8. |
A semiconductor using the hall effect will detect magnetic fields. |
A. | 1 |
B. | |
Answer» B. | |
9. |
A TRIAC will control AC voltage during the positive half cycle only. |
A. | 1 |
B. | |
Answer» C. | |
10. |
A TRIAC can be triggered or activated by either a positive or a negative input gate trigger. |
A. | 1 |
B. | |
Answer» B. | |
11. |
A silicon-controlled rectifier (SCR) has 3 terminals labeled base, collector, and emitter. |
A. | 1 |
B. | |
Answer» C. | |
12. |
An optically coupled isolator is a device containing _________ in a single package. |
A. | a photodiode and an optotransmitter |
B. | an LED and an SCR |
C. | an anode and a cathode |
D. | an IRED and a silicon phototransistor |
Answer» E. | |
13. |
To turn an SCR off, simply remove the gate voltage. |
A. | 1 |
B. | |
Answer» C. | |
14. |
The gate of a TRIAC can turn it on to have current flow in either direction. |
A. | 1 |
B. | |
C. | 1 |
D. | |
Answer» B. | |
15. |
A thermistor is a semiconductor device that acts like a piezoresistive resistor. |
A. | 1 |
B. | |
Answer» C. | |
16. |
What type of application would use an injection laser diode? |
A. | a 10BASE-T Ethernet |
B. | a liquid crystal display |
C. | a fiber optic transmission line |
D. | a good flashlight |
Answer» D. a good flashlight | |
17. |
A photodiode is a device that produces light. |
A. | 1 |
B. | |
Answer» C. | |
18. |
The DIAC conducts in only one direction when gated on. |
A. | 1 |
B. | |
C. | 1 |
D. | |
Answer» C. 1 | |
19. |
What type of application would use a photovoltaic cell? |
A. | an automobile horn |
B. | a TI 92 calculator |
C. | a magnetic field detector |
D. | a remote power source |
Answer» E. | |
20. |
The DIAC is a: |
A. | transistor |
B. | unidirectional device |
C. | three-layer device |
D. | bidirectional device |
Answer» E. | |
21. |
Once a DIAC is conducting, the only way to turn it off is with: |
A. | a positive gate voltage |
B. | a negative gate voltage |
C. | low-current dropout |
D. | breakover |
Answer» D. breakover | |
22. |
A transducer's function is to: |
A. | transmit electrical energy |
B. | convert energy |
C. | produce mechanical energy |
D. | prevent current flow |
Answer» C. produce mechanical energy | |
23. |
What is an SCR? |
A. | a PNPN thyristor with 3 terminals |
B. | a PNPN thyristor with 4 terminals |
C. | a PNP thyristor with 3 terminals |
D. | an NPN thyristor with 3 terminals |
Answer» B. a PNPN thyristor with 4 terminals | |
24. |
The only way to close an SCR is with: |
A. | a trigger input applied to the gate |
B. | forward breakover voltage |
C. | low-current dropout |
D. | valley voltage |
Answer» C. low-current dropout | |
25. |
What does a hall effect sensor sense? |
A. | temperature |
B. | moisture |
C. | magnetic fields |
D. | pressure |
Answer» D. pressure | |
26. |
When checking a good SCR or TRIAC with an ohmmeter it will: |
A. | show high resistance in both directions |
B. | show low resistance with positive on anode and negative on cathode, and high resistance when reversed |
C. | show high resistance with negative on anode and positive on cathode, and low resistance when reversed |
D. | show low resistance in both directions |
Answer» B. show low resistance with positive on anode and negative on cathode, and high resistance when reversed | |
27. |
The TRIAC is equivalent to ________________. |
A. | a four-layer diode |
B. | two DIACs in parallel |
C. | a thyristor with a gate lead |
D. | two SCRs in parallel |
Answer» E. | |
28. |
The PUT (programmable unijunction transistor) is actually a type of: |
A. | UJT thyristor |
B. | FET device |
C. | TRIAC |
D. | SCR |
Answer» B. FET device | |
29. |
What causes the piezoelectric effect? |
A. | heat or dissimilar metals |
B. | pressure on a crystal |
C. | water running on iron |
D. | a magnetic field |
Answer» C. water running on iron | |
30. |
The smallest amount of current that the cathode-anode can have, and still sustain conduction of an SCR is called the: |
A. | maximum forward current |
B. | maximum forward gate current |
C. | holding current |
D. | reverse gate leakage current |
Answer» E. | |
31. |
The optically coupled isolator interrupter module is used to transfer switching information between two electrically isolated points. |
A. | 1 |
B. | |
C. | 1 |
D. | |
Answer» C. 1 | |
32. |
A UJT has: |
A. | two base leads |
B. | one emitter lead |
C. | two emitter leads and one base lead |
D. | one emitter lead and two base leads |
Answer» E. | |
33. |
A TRIAC: |
A. | can trigger only on positive gate voltages |
B. | can trigger only on negative gate voltages |
C. | cannot be triggered with gate voltages |
D. | can be triggered by either a positive or a negative gate voltage |
Answer» E. | |