Thyristors and Tranducers MCQs : This section focuses on the "Thyristors and Tranducers". These Multiple Choice Questions (MCQs) should be practiced to improve the Thyristors and Tranducers skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
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
What causes the piezoelectric effect?
A. heat or dissimilar metals
B. pressure on a crystal
C. water running on iron
D. a magnetic field
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
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
The DIAC is a:
B. unidirectional device
C. three-layer device
D. bidirectional device
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
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
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
What does a hall effect sensor sense?
C. magnetic fields
A transducer's function is to:
A. transmit electrical energy
B. convert energy
C. produce mechanical energy
D. prevent current flow
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
The PUT (programmable unijunction transistor) is actually a type of:
A. UJT thyristor
B. FET device
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
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
Which is the DIAC?
Which is the seven-segment display?
Which is the TRIAC?