Q. All sine waves

  • (A) Have similar general appearance
  • (B) Have instantaneous rise and fall times
  • (C) Are in the same phase as cosine waves
  • (D) Rise instantly, but decay slowly
πŸ’¬ Discuss
βœ… Correct Answer: (A) Have similar general appearance

Q. The location of lighting arrestor is?

  • (A) Near the transformer
  • (B) Near the circuit breaker
  • (C) Away from the transformer
  • (D) None
πŸ’¬ Discuss
βœ… Correct Answer: (D) None

Q. The principle of operation of a 3 phase induction motor is most similar to that of a

  • (A) synchronous motor
  • (B) repulsion start induction motor
  • (C) transformer with a shorted secondary
  • (D) capacitor start, induction run motor
πŸ’¬ Discuss
βœ… Correct Answer: (C) transformer with a shorted secondary

Q. Which of the following is not a general characteristic of ac wave?

  • (A) The wave shape is identical for each cycle
  • (B) The polarity reverses periodically
  • (C) The electrons always flow in the same direction
  • (D) There is a definite frequency
πŸ’¬ Discuss
βœ… Correct Answer: (C) The electrons always flow in the same direction

Q. A battery has a short-circuit current of 30A and an open circuit voltage of 24V. If the battery is connected to an electric bulb of resistance 2 ?, the power dissipated by the bulb is

  • (A) 80W
  • (B) 1800W
  • (C) 112.5W
  • (D) 228W
πŸ’¬ Discuss
βœ… Correct Answer: (C) 112.5W

Q. A battery is source of

  • (A) DC voltage
  • (B) 1 phase AC voltage
  • (C) 3 phase ac voltage
  • (D) ac or dc voltage
πŸ’¬ Discuss
βœ… Correct Answer: (A) DC voltage

Q. A BJT has

  • (A) three PN junctions
  • (B) three semiconductor layers
  • (C) two N type layers around a P type layer
  • (D) a low avalanche voltage
πŸ’¬ Discuss
βœ… Correct Answer: (B) three semiconductor layers

Q. A capacitor is charged by a constant current of 2mA and results in a voltage increase of 12V in a 10 sec interval. The value of capacitance is

  • (A) 0.75mF
  • (B) 1.33mF
  • (C) 0.6mF
  • (D) 1.67mF
πŸ’¬ Discuss
βœ… Correct Answer: (D) 1.67mF

Q. A common-collector transistor circuit is often used

  • (A) to provide high gain and sensitivity over a wide range of frequencies
  • (B) to match a high impedance to a low impedance
  • (C) as a high-fidelity audio power amplifier
  • (D) as an oscillator at microwaves frequencies
πŸ’¬ Discuss
βœ… Correct Answer: (B) to match a high impedance to a low impedance

Q. A complex wave form made up frequency components 1 Hz, 3 Hz, 5 Hz, 7 Hz and 9 Hz. Its fundamental frequency is

  • (A) 9 Hz
  • (B) 12.5 Hz
  • (C) 1 Hz
  • (D) Indeterminate
πŸ’¬ Discuss
βœ… Correct Answer: (C) 1 Hz

Jump to