Licensed Electrical Contractor Electrical Theory & Fundamentals 2

Question 1

What happens to the total resistance when resistors are connected in parallel?

Accepted Answer

It is always less than the smallest resistor

Answer

In a parallel circuit, the total resistance is always less than the smallest individual resistor because current has multiple paths.

Question 2

A conductor has a resistance of 10 ohms at 20°C. If the temperature increases, what happens to its resistance?

Accepted Answer

Increases, because higher temperature increases atomic vibration

Answer

For most metallic conductors, resistance increases with temperature due to increased atomic vibration impeding electron flow.

Question 3

What is the unit of electrical capacitance?

Accepted Answer

Farad

Answer

The farad (F) is the SI unit of capacitance, measuring a capacitor's ability to store electric charge.

Question 4

In an AC circuit, what does the term 'reactance' refer to?

Accepted Answer

Opposition to current flow by inductors or capacitors

Answer

Reactance is the opposition to AC current caused by inductance (XL) or capacitance (XC), measured in ohms but unlike resistance it stores rather than dissipates energy.

Question 5

What is the relationship between frequency and inductive reactance (XL)?

Accepted Answer

XL increases as frequency increases

Answer

Inductive reactance XL = 2πfL, so it is directly proportional to frequency — as frequency increases, XL increases.

Licensed Electrical Contractor Practice Test

Licensed Electrical Contractor Practice Test

Licensed Electrical Contractor Electrical Theory & Fundamentals 2