Journeyman Electrician’s Exam Transformers and Electrical Theory 2

Question 1

What is the power factor of a purely resistive AC circuit?

Accepted Answer

1.0

Answer

0

Answer

0.5

Answer

0.707

Question 2

Apparent power in an AC circuit is expressed in which unit?

Accepted Answer

Volt-amperes (VA)

Answer

Watts (W)

Answer

Volt-amperes reactive (VAR)

Answer

Kilowatts (kW)

Question 3

A circuit has 240V applied and draws 20 amperes. Using Ohm's Law, what is the circuit resistance?

Accepted Answer

12 ohms

Answer

4,800 ohms

Answer

260 ohms

Answer

20 ohms

Question 4

What is the correct formula for calculating true (real) power in a single-phase AC circuit?

Accepted Answer

P = V × I × PF

Answer

P = V × I

Answer

P = V × I × 1.732

Answer

P = V × I × 2

Question 5

A series circuit has a resistance of 6 ohms and an inductive reactance of 8 ohms. What is the total impedance?

Accepted Answer

10 ohms

Answer

14 ohms

Answer

2 ohms

Answer

48 ohms

Question 6

What is the inductive reactance (XL) of a 0.2 Henry inductor at 60 Hz?

Accepted Answer

75.4 ohms

Answer

12 ohms

Answer

37.7 ohms

Answer

120 ohms