Electrical Theory Flashcards

In National Joint Apprenticeship and Training Committee, what is Ohm's Law?

Answer: V = I × R (Voltage equals Current times Resistance)

Ohm's Law states that voltage (V) equals current (I) multiplied by resistance (R). This fundamental relationship is essential for calculating electrical values in any circuit.

What is the purpose of a circuit breaker in National Joint Apprenticeship and Training Committee electrical theory?

Answer: To automatically interrupt electrical flow when current exceeds safe levels

Circuit breakers are safety devices that automatically disconnect the circuit when current exceeds rated levels, protecting wiring and equipment from overload damage and reducing fire risk.

In National Joint Apprenticeship and Training Committee, what is the difference between series and parallel circuits?

Answer: Series: components share one path; Parallel: components have separate paths

In a series circuit, components are connected in a single path so the same current flows through each. In parallel circuits, components have separate paths, sharing the same voltage but dividing the current.

What does "grounding" mean in National Joint Apprenticeship and Training Committee electrical systems?

Answer: Providing a safe path for fault current to flow to earth, preventing electrical shock

Grounding creates a low-resistance path for fault current to flow safely to earth, protecting people from electrical shock and allowing protective devices to quickly disconnect faulted circuits.

In National Joint Apprenticeship and Training Committee, what is alternating current (AC)?

Answer: Electrical current that periodically reverses direction

Alternating current (AC) periodically reverses direction, typically at 60 Hz (US) or 50 Hz (other countries). AC is used for power distribution because it can be efficiently transformed to different voltage levels.

What is the National Electrical Code (NEC) in National Joint Apprenticeship and Training Committee?

Answer: A comprehensive standard for safe electrical installation and practices in the US

The NEC (NFPA 70) is a widely adopted standard that establishes requirements for safe electrical installations, covering wiring methods, grounding, overcurrent protection, and equipment specifications.