TEST PAPER 2026 COMPLETE QUESTIONS AND
ANSWERS EXPERT VERIFIED GRADED A+
◉ An SCR conducts when: Answer: Gate is triggered and forward
biased | Reverse biased | Gate removed | AC removed
◉ Once an SCR is on, it stays on until: Answer: Current drops below
holding current | Gate removed | Voltage rises | Load increases
◉ Holding current is: Answer: Minimum current to keep SCR on |
Trigger current | Peak current | Load current
◉ A TRIAC conducts during: Answer: Both halves of AC | Positive
half only | Negative only | DC only
◉ A DIAC is used to: Answer: Trigger a TRIAC | Rectify | Regulate |
Amplify
◉ Phase control works by: Answer: Delaying conduction angle |
Increasing voltage | Filtering ripple | Regulating DC
, ◉ Delaying firing angle will: Answer: Reduce power | Increase
power | Increase frequency | Stop current
◉ An op-amp amplifies: Answer: Voltage | Current | Frequency |
Power
◉ An op-amp has how many inputs? Answer: Two | One | Three |
Four
◉ Inverting input causes output to be: Answer: Inverted | In phase |
Zero | Clipped
◉ Non-inverting input causes output to be: Answer: In phase |
Inverted | Zero | Saturated
◉ Negative feedback is used to: Answer: Control gain and stability |
Increase distortion | Turn off | Rectify
◉ If feedback opens, op-amp output will: Answer: Saturate |
Regulate | Follow input | Oscillate slightly
◉ A comparator output will: Answer: Saturate high or low | Regulate
voltage | Filter ripple | Amplify AC