Download TEXAS (TX) Journeyman Electrician Exam and more Exams Technology in PDF only on Docsity!
Question 1. Which fundamental law states that the total current entering a junction equals the total current leaving the junction? A) Ohm's Law B) Kirchhoff's Current Law (KCL) C) Faraday's Law D) Coulomb's Law Answer: B Explanation: Kirchhoff's Current Law (KCL) asserts that the algebraic sum of currents entering a junction equals zero, meaning total current entering equals total current leaving, ensuring conservation of electric charge. Question 2. In an electrical circuit, voltage is best described as: A) The flow of electrons B) The electrical potential difference between two points C) The opposition to current flow D) The rate at which energy is transferred Answer: B Explanation: Voltage, or electrical potential difference, measures the energy difference per unit charge between two points in a circuit, driving current flow. Question 3. Which type of current is characterized by a unidirectional flow and is commonly used in batteries? A) AC (Alternating Current)
B) DC (Direct Current) C) Pulsating current D) Static electricity Answer: B Explanation: Direct Current (DC) flows in a single direction, typical of batteries, whereas AC alternates direction periodically. Question 4. In a series circuit, the total resistance is: A) Equal to the sum of individual resistances B) The reciprocal of the sum of conductances C) Equal to the smallest resistance D) Independent of individual resistances Answer: A Explanation: In series, resistances add directly, so the total resistance equals the sum of all resistances. Question 5. The unit of electrical power is: A) Volt B) Ampere C) Watt D) Ohm Answer: C
Question 8. A transformer operates on which principle? A) Mechanical induction B) Magnetic induction C) Chemical reaction D) Thermal conduction Answer: B Explanation: Transformers operate based on electromagnetic induction, transferring energy between circuits via magnetic fields. Question 9. Which phase system has three separate sinusoidal voltages separated by 120 degrees? A) Single-phase system B) Two-phase system C) Three-phase system D) Polyphase system Answer: C Explanation: A three-phase system uses three sinusoidal voltages, each separated by 120°, providing balanced power delivery. Question 10. In electrical symbols, a zigzag line typically represents: A) Resistor B) Capacitor
C) Inductor D) Switch Answer: A Explanation: A zigzag line symbolizes a resistor in electrical schematics. Question 11. PPE includes all EXCEPT: A) Insulating gloves B) Safety glasses C) Voltage testers D) Overalls and arc flash clothing Answer: C Explanation: Voltage testers are tools used to verify voltage presence; PPE refers to personal protective equipment worn for safety. Question 12. Lockout/Tagout procedures are used to: A) Prevent electrical fires B) Isolate energy sources during maintenance C) Increase circuit capacity D) Reduce electrical noise Answer: B Explanation: Lockout/Tagout procedures ensure that energy sources are isolated and secured to prevent accidental energization during servicing.
C) Providing electrical training D) Designing electrical systems Answer: B Explanation: The AHJ is the local authority responsible for interpreting and enforcing electrical codes and standards. Question 16. The term "grounded" refers to: A) An unconnected conductor B) Connected to earth or a conductive body that serves as a reference point C) A conductor with high resistance D) A conductor that carries current Answer: B Explanation: Grounding provides a reference point to earth, enhancing safety and system stability. Question 17. A branch circuit is defined as: A) A circuit feeding a single device from a panelboard B) The main service entrance conductors C) A circuit serving multiple buildings D) The main power source for a structure Answer: A
Explanation: Branch circuits originate at the panelboard and supply power to outlets or devices. Question 18. The purpose of a neutral conductor is to: A) Carry unbalanced load currents back to the source B) Provide a ground path C) Isolate the circuit from the power source D) Serve as a phase conductor Answer: A Explanation: The neutral conductor completes the circuit by returning current to the source, especially under unbalanced loads. Question 19. Multi-wire branch circuits are permitted when: A) All conductors are protected by a common overcurrent device and are from the same panel B) They serve multiple buildings C) Conductors are insulated with different materials D) The circuit is exclusively for lighting Answer: A Explanation: Multi-wire branch circuits are allowed if conductors are from the same panel and protected by a common overcurrent device, ensuring balanced loads.
D) Protect against voltage surges Answer: B Explanation: The disconnect allows the entire electrical service to be shut off for safety during repairs or emergencies. Question 23. Overcurrent protection devices include: A) Fuses and circuit breakers B) Transformers and capacitors C) Resistors and relays D) Switches and relays Answer: A Explanation: Fuses and circuit breakers are devices designed to protect conductors and equipment from overcurrent conditions. Question 24. An overcurrent device should be located: A) As far from the load as possible B) Near the power source or panelboard for easy access and protection C) Only at the load end of the circuit D) Inside the conduit bend Answer: B Explanation: Overcurrent devices should be accessible and located close to the power source or in the panel for effective protection and maintenance.
Question 25. The purpose of grounding is to: A) Provide a low-resistance path for fault current B) Increase circuit voltage C) Prevent circuit overloads D) Reduce power consumption Answer: A Explanation: Grounding provides a safe path for fault current, reducing shock hazards and protecting equipment. Question 26. A grounding electrode system includes all of the following EXCEPT: A) Ground rods B) Metal water piping C) Concrete-encased electrodes D) Insulated conductors Answer: D Explanation: Insulated conductors are not electrodes; electrodes are conductive elements like rods or pipes driven into earth. Question 27. The correct sizing of equipment grounding conductors is based on: A) The size of the overcurrent device protecting the circuit B) The length of the conductor
Explanation: NM cable, like Romex, is commonly used for concealed residential wiring due to ease of installation. Question 30. The minimum bend radius for flexible conduit is generally: A) Equal to the conduit diameter B) Twice the conduit diameter C) One-half the conduit diameter D) The same as the conduit length Answer: B Explanation: To prevent damage or undue stress, the minimum bend radius is typically at least twice the diameter of the conduit. Question 31. Conductor ampacity ratings can be adjusted based on: A) Ambient temperature and bundling factors B) Length of the conductor only C) The color of the insulation D) The voltage supplied to the circuit Answer: A Explanation: Ampacity adjustments are made considering ambient temperature, conductor bundling, and other conditions affecting heat dissipation. Question 32. Which of the following is NOT a typical type of raceway?
A) EMT (Electrical Metallic Tubing) B) Rigid PVC conduit C) Flexible plastic tubing D) Rigid RMC (Rigid Metal Conduit) Answer: C Explanation: Flexible plastic tubing is not recognized as a raceway; flexible conduits are used, but not as tubing. Question 33. Box fill calculations are performed to determine: A) The maximum number of conductors and devices in a box B) The voltage rating of the box C) The weight of the box per square foot D) The temperature rating of the box Answer: A Explanation: Box fill calculations ensure that the box has sufficient capacity for all conductors, devices, and fittings to prevent overcrowding. Question 34. An NM cable is permitted to be used: A) In wet locations without protection B) Inside walls in dry locations C) Under concrete slabs D) As a direct burial cable in all conditions
Question 37. Which of the following is an example of a luminaire? A) A ceiling-mounted light fixture B) An electrical switch C) A receptacle outlet D) A circuit breaker Answer: A Explanation: A luminaire is a complete lighting unit, such as a ceiling fixture or lamp. Question 38. Receptacle spacing in a dwelling must be: A) No more than 12 feet apart in habitable rooms B) Exactly 6 feet apart throughout the house C) Only on exterior walls D) Placed only near the ceiling Answer: A Explanation: NEC requires receptacles to be spaced so that no point along the wall is more than 6 feet from a receptacle, effectively 12-foot intervals. Question 39. An overload in a motor circuit causes: A) Excessive current that may damage the motor B) A reduction in motor speed C) The motor to operate more efficiently
D) No effect on the motor Answer: A Explanation: Overloads result in excessive current, which can cause overheating and potential damage to the motor. Question 40. The purpose of a motor overload relay is to: A) Protect the motor from overheating due to overload conditions B) Increase motor speed C) Reduce starting current D) Convert AC to DC power for the motor Answer: A Explanation: Overload relays disconnect power to prevent overheating when the motor draws excessive current over time. Question 41. A transformer that steps voltage down from a higher to a lower voltage is called: A) Step-up transformer B) Step-down transformer C) Isolation transformer D) Autotransformer Answer: B
A) Store electrical energy temporarily and filter signals B) Limit current flow C) Convert AC to DC D) Provide a path for fault current Answer: A Explanation: Capacitors store electrical energy and are used for filtering, power factor correction, and energy storage. Question 45. Storage batteries in electrical systems are used to: A) Store electrical energy for backup or load leveling B) Step down voltage C) Convert AC to DC D) Protect against surges Answer: A Explanation: Batteries store electrical energy for backup power, ensuring system operation during outages. Question 46. Which of the following is a common application for a three-phase motor? A) Air conditioning systems B) Residential lighting circuits C) Small appliances D) Single-family dwelling circuits
Answer: A Explanation: Three-phase motors are used in industrial and large commercial applications like HVAC systems due to their efficiency and power capacity. Question 47. The purpose of a disconnecting means for a motor is to: A) Isolate the motor for maintenance and emergency shutdowns B) Provide overload protection C) Step the voltage down for the motor D) Increase starting torque Answer: A Explanation: The disconnecting means allows safe disconnection of the motor for servicing or emergencies. Question 48. Which article of the NEC covers the requirements for motor circuits and controllers? A) Article 430 B) Article 210 C) Article 250 D) Article 300 Answer: A Explanation: Article 430 addresses motor circuit wiring, protection, and control requirements.
