NEC General Electrical Theory & Code Definitions

Question 1

What is the unit of electrical resistance?

Accepted Answer

Ohm

Answer

In electrical engineering, the ohm (Ω) is the SI derived unit of electrical resistance. It quantifies how much an object or material opposes the flow of electric current. Understanding resistance is fundamental to analyzing and designing electrical circuits, as described by Ohm's Law.

Question 2

What does Article 100 of the NEC cover?

Accepted Answer

Definitions

Answer

Article 100 of the National Electrical Code (NEC) is specifically dedicated to providing comprehensive definitions for terms used throughout the code. This foundational article ensures consistent understanding and application of the NEC's requirements across all electrical installations. Clear definitions are crucial for accurate interpretation and compliance.

Question 3

Which law explains the relationship between voltage, current, and resistance?

Accepted Answer

Ohm’s Law

Answer

Ohm's Law is a fundamental principle in electrical circuits that describes the relationship between voltage, current, and resistance. It states that the current through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance between them (V = IR). This law is essential for understanding and calculating electrical circuit parameters.

Question 4

What is the basic unit of electric current?

Accepted Answer

Ampere

Answer

The ampere (A), often shortened to 'amp,' is the basic SI unit of electric current. It measures the rate of flow of electric charge past a point in an electrical circuit. Understanding the ampere is fundamental to electrical engineering and is a key component in calculations involving power and resistance.

Question 5

Which NEC article outlines general requirements for electrical installations?

Accepted Answer

Article 110

Answer

NEC Article 110, titled 'Requirements for Electrical Installations,' outlines the general requirements applicable to all electrical installations. It covers crucial aspects such as the examination, identification, installation, and use of electrical equipment. This article serves as a foundational guide to ensure safety and proper functionality in electrical systems.

NEC Practice Test

NEC Practice Test

NEC General Electrical Theory & Code Definitions