Electrical Contractor Electrical Theory & Fundamentals

Question 1

What is the relationship between voltage, current, and resistance?

Accepted Answer

Voltage equals current multiplied by resistance.

Answer

This relationship is known as Ohm's Law, a fundamental principle in electrical engineering. It states that the voltage (V) across a conductor is directly proportional to the current (I) flowing through it, with the constant of proportionality being the resistance (R), expressed as V = I * R.

Question 2

What is the unit of electrical resistance?

Accepted Answer

Ohms.

Answer

Ohms (Ω) are the standard unit of electrical resistance, named after Georg Simon Ohm. Resistance measures how much a material opposes the flow of electric current, and it is a crucial factor in determining current flow and voltage drop in an electrical circuit.

Question 3

Which of the following best describes an electrical circuit?

Accepted Answer

A path that allows current to flow from a power source to a load and back to the source.

Answer

An electrical circuit is a complete, closed loop that enables electric current to flow continuously. It consists of a power source (like a battery or generator), conductors (wires), a load (a device that uses electricity), and a return path, ensuring the uninterrupted circulation of electrons.

Question 4

What is the purpose of a capacitor in an electrical circuit?

Accepted Answer

To store and release electrical energy.

Answer

A capacitor is a passive electronic component that stores electrical energy in an electric field between two conductive plates separated by a dielectric material. It can then rapidly release this stored energy, making it useful for filtering, timing, and power conditioning in various electronic circuits.

Question 5

What is the function of an inductor in a circuit?

Accepted Answer

To resist changes in current and store energy in a magnetic field.

Answer

An inductor is a passive electrical component that stores energy in a magnetic field when current flows through it. Its primary function is to oppose changes in the current flowing through it, a property known as inductance, which makes it useful for filtering, tuning, and energy storage in AC circuits.

Licensed Electrical Contractor Practice Test

Licensed Electrical Contractor Practice Test

Electrical Contractor Electrical Theory & Fundamentals