ELECTRICAL ORAL QUESTIONS FOR G.P. RATING

Basic Electricity Oral Questions for GP Rating

1. What is electricity?
   → Electricity is the flow of electric charge (electrons) through a conductor, like a wire.
2. What is voltage?
   → Voltage is the electrical pressure that pushes current through a circuit. It is measured in volts (V).
3. What is current?
   → Current is the flow of electrons in a circuit. It is measured in amperes (A).
4. What is resistance?
   → Resistance is the opposition to the flow of current in a circuit. It is measured in ohms (Ω).
5. What is the unit of power?
   → The unit of electrical power is the watt (W).
6. What is Ohm’s Law?
   → Ohm’s Law: V = I × R, where:
   
   • V = Voltage
   • I = Current
   • R = Resistance
7. What is the difference between AC and DC?
   → AC (Alternating Current): Current changes direction periodically.
   → DC (Direct Current): Current flows in one direction only.
8. What is a fuse?
   → A fuse is a safety device that breaks the circuit when current exceeds the safe limit to prevent damage or fire.
9. What is a circuit breaker?
   → A circuit breaker is an automatic switch that turns off the electrical circuit during overload or short circuit.
10. What is the function of an earth wire?
    → Earth wire provides a path for excess current to safely go into the ground and protects against electric shock.
11. What is a short circuit?
    → A short circuit happens when a live wire touches a neutral or ground wire, causing excess current flow and possible damage.
12. Why is insulation important?
    → Insulation prevents current from leaking and protects people from electric shock.
13. Name any two types of electrical hazards.
    → Electric shock, Fire due to short circuit.
14. What is a generator?
    → A generator converts mechanical energy into electrical energy.
15. What precautions should you take while working with electricity onboard?
    → Use dry hands, wear safety gear, ensure power is off before touching wires, and follow ship’s safety procedures.

⚡ Additional Basic Electricity Oral Questions for GP Rating

16.  What is a conductor?
→ A conductor is a material that allows electric current to pass through easily (e.g., copper, aluminum).

17.  What is an insulator?
→ An insulator is a material that does not allow current to pass through (e.g., rubber, plastic, glass).

18.  What is the purpose of a switch?
→ A switch is used to open or close an electrical circuit to control the flow of current.

19.  What is the function of a multimeter?
→ A multimeter is used to measure voltage, current, and resistance in an electrical circuit.

20.  What is the standard voltage used onboard ships?
→ Ships may use 110V, 220V, or 440V AC, depending on the system.

21.  What is a battery?
→ A battery stores electrical energy in chemical form and provides DC power.

22.  What is polarity in electricity?
→ Polarity refers to the positive (+) and negative (–) terminals in a DC circuit.

23.  What is an electric motor?
→ A motor converts electrical energy into mechanical energy (used to run pumps, fans, etc.).

24.  What is grounding or earthing?
→ Grounding means connecting the electrical system to the earth to prevent electric shock.

25.  What happens if you touch a live wire?
→ You may receive an electric shock, which can be dangerous or fatal.

26.  Name any two personal protective equipment (PPE) used during electrical work.
→ Insulated gloves, safety shoes.

27.  What is the color coding of electrical wires?
→ Generally:

·         Red or Brown – Live wire

·         Black or Blue – Neutral wire

·         Green/Yellow – Earth wire
(Color codes may vary by country/ship.)

28.  What should you do if someone gets an electric shock?
→ Switch off the power, use a non-conductive stick to move the person, and call for medical help.

29.  What is an overload?
→ Overload happens when too much current flows through a circuit, which can overheat wires and damage equipment.

30.  What is a capacitor?
→ A capacitor stores electrical energy and is used in circuits for various functions like starting motors.

31.  What is an inverter?
→ An inverter converts DC to AC power.

32.  What is a transformer?
→ A transformer is used to increase (step-up) or decrease (step-down) voltage in AC circuits.

33.  Why is electrical equipment bonded to the hull on a ship?
→ To prevent static electricity buildup and ensure safety during faults.

34.  Why is 440V dangerous?
→ It is a high voltage and can cause severe electric shock or burns.

35.  What is a solenoid?
→ A solenoid is a coil of wire that acts like a magnet when electricity flows through it.

36. What is the function of a relay?
    → A relay is an electrically operated switch used to control a high-power circuit with a low-power signal.
37. What is a diode?
    → A diode allows current to flow in only one direction.
38. What is the function of a circuit diagram?
    → A circuit diagram shows the components and wiring of an electrical circuit for easy understanding and maintenance.
39. What is a terminal block?
    → A terminal block is used to connect wires together safely in an electrical panel.
40. Why is proper lighting important in the engine room?
    → To ensure safe working conditions and avoid accidents or errors while working on machinery.
41. What is a three-phase supply?
    → A three-phase supply has three alternating currents, each 120° apart, providing more power efficiently.
42. What is a single-phase supply?
    → A single-phase supply has only one alternating current and is used for smaller loads.
43. What is meant by ‘live’ wire?
    → A live wire carries current from the power source to the equipment.
44. What is a ‘neutral’ wire?
    → A neutral wire completes the circuit by carrying current back to the power source.
45. What is a megger?
    → A megger (megohmmeter) is used to measure insulation resistance of electrical cables.
46. What does LUX mean in lighting?
    → Lux is the unit of light intensity. It measures the amount of light on a surface.
47. Why are emergency lights provided on-board?
    → To provide lighting during power failure or blackout for safe evacuation and emergency operations.
48. What is a load?
    → A load is any electrical device or equipment that consumes electrical power.
49. What is a power factor?
    → Power factor is the ratio between real power and apparent power. A high power factor means efficient power usage.
50. What are the dangers of using a damaged extension cord?
    → Risk of short circuit, electric shock, or fire hazard.
51. Why are electrical panels kept locked onboard?
    → To prevent unauthorized access and ensure safety.
52. What is an ELCB or RCCB?
    → ELCB (Earth Leakage Circuit Breaker) and RCCB (Residual Current Circuit Breaker) are safety devices that cut power during earth leakage.
53. What is static electricity?
    → Static electricity is the buildup of electrical charge on the surface of objects, which can cause sparks.
54. What is bonding?
    → Bonding is the electrical connection between metallic parts to equalize potential and avoid sparks.
55. Why is regular electrical maintenance important on a ship?
    → To ensure safety, avoid breakdowns, and comply with maritime regulations.

 

🔌 Basic Questions on Electric Resistance for GP Rating Oral Exam

1.      What is resistance?
→ Resistance is the opposition to the flow of electric current in a circuit.

2.      What is the unit of resistance?
→ The unit of resistance is Ohm (Ω).

3.      What instrument is used to measure resistance?
→ Resistance is measured using an Ohmmeter or Multimeter.

4.      What is the symbol of resistance in a circuit diagram?
→ The symbol is a zig-zag line (R).

5.      Which materials have high resistance?
→ Insulators like rubber, plastic, and glass have high resistance.

6.      Which materials have low resistance?
→ Conductors like copper, aluminum, and silver have low resistance.

7.      What is the effect of resistance on current?
→ Higher resistance means less current flows.
→ Lower resistance means more current flows.

8.      What is Ohm’s Law?
→ V = I × R, where:

o    V = Voltage

o    I = Current

o    R = Resistance

9.      What happens if resistance increases in a circuit?
→ Current decreases, and some energy may be lost as heat.

10.  Why are resistors used in electrical circuits?
→ To control or limit the current flow and protect components.

11.  Does the length of a wire affect resistance?
→ Yes. Longer wires have more resistance.

12.  Does the thickness of a wire affect resistance?
→ Yes. Thicker wires have less resistance.

13.  What is the relationship between resistance and temperature?
→ In most conductors, resistance increases with temperature.

14.  Why does a fuse wire have high resistance?
→ So it heats up and melts quickly when excess current flows, breaking the circuit for safety.

15.  Give an example of where resistance is useful onboard.
→ Electric heaters and toaster coils work based on resistance heating.