Multiple Choice Questions and Answers on SCR
Last Updated on January 9, 2020 by Sasmita
Multiple Choice Questions and Answers on SCR (Silicon Controlled Rectifiers)
In addition to reading the questions and answers on my site, I would suggest you to check the following, on amazon, as well:
- Question Bank in Electronics & Communication Engineering by Prem R Chadha
- A Handbook on Electronics Engineering – Illustrated Formulae & Key Theory Concepts
Q1. An SCR has …………….. pn junctions
- Two
- Three
- Four
- None of the above
Answer : 2
Q2. An SCR is a solid state equivalent of …………….
- Triode
- Pentode
- Gas-filled triode
- Tetrode
Answer : 3
Q3. An SCR has ………….. semiconductor layers
- Two
- Three
- Four
- None of the above
Answer : 3
Q4. An SCR has three terminals viz ……………
- Cathode, anode, gate
- Anode, cathode, grid
- Anode, cathode, drain
- None of the above
Answer : 1
Q5. An SCR behaves as a ……………. switch
- Unidirectional
- Bidirectional
- Mechanical
- None of the above
Answer : 1
Q6. An SCR is sometimes called …………
- Triac
- Diac
- Unijunction transistor
- Thyristor
Answer : 4
Q7. An SCR is made of ………….
- Germanium
- Silicon
- Carbon
- None of the above
Answer : 2
Q8. In the normal operation of an SCR, anode is …………… w.r.t. cathode
- At zero potential
- Negative
- Positive
- None of the above
Answer : 3
Q9. In normal operation of an SCR, gate is ………..w.r.t. cathode
- Positive
- Negative
- At zero potential
- None of the above
Answer : 1
Q10. An SCR combines the features of …………..
- A rectifier and resistance
- A rectifier and transistor
- A rectifier and capacitor
- None of the above
Answer : 2
Q11. The control element of an SCR is ………….
- Cathode
- Anode
- Anode supply
- Gate
Answer : 4
Q12. The normal way to turn on a SCR is by ……………..
- Breakover voltage
- Appropriate anode current
- Appropriate gate current
- None of the above
Answer : 3
Q13. An SCR is turned off by …………….
- Reducing anode voltage to zero
- Reducing gate voltage to zero
- Reverse biasing the gate
- None of the above
Answer : 1
Q14. An SCR is a ……………….. triggered device
- Voltage
- Current
- Voltage as well as current
- None of the above
Answer : 2
Q15. In an SCR circuit the supply voltage is generally ……….. that of breakover voltage
- Equal to
- Less than
- Greater than
- None of the above
Answer : 2
Q16. When an SCR is turned on, the voltage across it is about ……….
- Zero
- 10 V
- 1 V
- 1 V
Answer : 4
Q17. An SCR is made of silicon and not germanium because silicon ………
- Is inexpensive
- Is mechanically strong
- Has small leakage current
- Is tetravalent
Answer : 3
Q18. An SCR is turned off when …………..
- Anode current is reduced to zero
- Gate voltage is reduced to zero
- Gate is reverse biased
- None of the above
Answer : 1
Q19. In an SCR circuit, the angle of conduction can be changed by ……….
- Changing anode voltage
- Changing gate voltage
- Reverse biasing the gate
- None of the above
Answer : 2
Q20. If firing angle in an SCR circuit is increased, the output …………
- Remains the same
- Is increased
- Is decreased
- None of the above
Answer : 3
Q21. If gate current is increased, then anode-cathode voltage at which SCR closes …………….
- Is decreased
- Is increased
- Remains the same
- None of the above
Answer : 1
Q22. When SCR is OFF, the current in the circuit is …………….
- Exactly zero
- Small leakage current
- Large leakage current
- None of the above
Answer : 2
Q23. An SCR can exercise control over ………. of a.c. supply
- Positive half-cycles only
- Negative half-cycles only
- Both positive and negative half-cycles
- Positive or negative half-cycles
Answer : 4
Q24. We can control a.c. power in a load by connecting …………
- Two SCRs in series
- Two SCRs in parallel
- Two SCRs in parallel opposition
- None of the above
Answer : 3
Q25. When SCR starts conducting, then ……………. loses all control
- Gate
- Cathode
- Anode
- None of the above
Answer : 1
Check out the ultimate resource on Basic Electronics Questions and Answers . With hundreds of chapter-wise questions & answers on Basic Electronics, this is the most comprehensive question bank on the entire internet.
In addition to reading the questions and answers on my site, I would suggest you to check the following, on amazon, as well: