Trade-based questions for ITI trades such as electrician, fitter, mechanic, electronics mechanic, turner, machinist, wireman, welder, refrigeration and AC and other notified trades - One Line Questions

1. In a three-phase AC system, what is the phase difference between any two consecutive phases? 120 degrees
2. Which type of AC welding machine provides a constant current output suitable for Stick welding? AC Transformer machine
3. What is the main component of refrigerant in most common air conditioning systems? Freon (e.g., R-22, R-410A)
4. Which law states that the induced EMF in any closed circuit is equal to the negative of the time rate of change of the magnetic flux enclosed by the circuit? Faraday's Law of Induction
5. What is the process of joining two or more pieces of metal by melting them together, often with the addition of a filler metal? Welding
6. Which safety device is designed to protect electrical circuits from overcurrent by melting and breaking the circuit? Fuse
7. In a refrigeration cycle, which component is responsible for absorbing heat from the refrigerated space? Evaporator
8. Which type of wiring is used for temporary installations or where flexibility is required? Flexible wiring
9. Which type of AC generator produces AC power at a constant frequency, irrespective of the load? Synchronous generator
10. Which type of motor has its rotor speed directly proportional to the supply frequency and inversely proportional to the number of poles? Synchronous motor
11. In a DC generator, the polarity of the generated EMF is determined by: Fleming's Right-Hand Rule
12. What is the process of removing unwanted material from a workpiece by using a cutting tool? Machining
13. What does the 'star' connection in a three-phase transformer provide? Neutral point for grounding
14. What is the SI unit of power? Watt
15. What is the most common type of winding used in squirrel cage induction motors? Squirrel cage winding
16. Which of the following is a measure of the amount of heat energy required to raise the temperature of a unit mass of a substance by one degree Celsius? Specific heat capacity
17. Which type of circuit breaker is commonly used in residential distribution boards for overload and short-circuit protection? Miniature Circuit Breaker (MCB)
18. Which tool is used to measure the diameter of a hole or the internal dimension of an object? Vernier caliper
19. What is the primary characteristic of Ohm's Law? Voltage is equal to current times resistance
20. What is a transistor primarily used for in electronic circuits? Amplification and switching
21. Which of the following is a semiconductor device that can amplify or switch electronic signals? Transistor
22. Which type of welding uses a non-consumable tungsten electrode and a shielding gas? Gas Tungsten Arc Welding (GTAW)
23. What is the main advantage of a switch-mode power supply (SMPS) over a linear power supply? Higher efficiency and smaller size
24. Which type of welding uses a consumable wire electrode and a shielding gas? GMAW
25. Which type of file is used for rough shaping and rapid material removal? Bastard file
26. What is the term for the amount of heat required to change the state of a substance (e.g., solid to liquid) without changing its temperature? Latent heat
27. Which type of AC motor is widely used due to its simple construction, robustness, and low cost? Induction motor
28. Which measurement is used to determine the hardness of metals? Rockwell hardness test
29. In electronics, what is the primary function of a diode? To allow current to flow in one direction only
30. What is the primary function of a transformer? To increase or decrease AC voltage
31. What is the function of a commutator in a DC generator? To convert AC to DC
32. What is the purpose of a rectifier circuit? To convert AC to DC
33. What is the function of the condenser in a refrigeration system? To cool the refrigerant
34. In a refrigeration system, what is the role of the compressor? To increase the pressure and temperature of the refrigerant vapor
35. In a fitter's trade, what is the purpose of a die? To cut external threads
36. In a turner's lathe, what is the purpose of the tailstock? To support long workpieces and hold cutting tools for operations like drilling
37. What is the purpose of annealing in metalworking? To reduce brittleness and improve ductility
38. What is the purpose of the slag in an electrode during SMAW (Stick Welding)? To protect the molten weld pool from atmospheric contamination
39. What is the main purpose of flux in soldering? To clean the metal surfaces and prevent oxidation
40. What is the function of a vernier scale on a measuring instrument? To provide a finer reading with greater accuracy
41. What is the primary function of a commutator in a DC motor? To reverse the direction of current in the armature windings
42. In a three-phase induction motor, what is the function of the slip? To allow the rotor to rotate at a speed less than the synchronous speed, inducing current
43. What is the primary function of a regulator in an electrical system? To maintain a constant output voltage
44. What is the function of a capacitor in an electronic circuit? To store electrical energy in an electric field
45. What is the purpose of the starter in a fluorescent lamp? To provide a high voltage pulse to initiate the arc
46. What is the function of an expansion valve in a refrigeration system? To regulate the flow of refrigerant into the evaporator
47. What is the purpose of the stator in an AC motor? To provide the rotating magnetic field
48. What is the primary role of an inductor in an electronic circuit? To store energy in a magnetic field
49. Which tool is used to measure the outside diameter of a cylindrical object with high precision? Micrometer
50. What is the unit of electrical resistance? Ohm