Journeyman Electrician’s Exam Journeyman Electrician's Basic Formula 2

Question 1

A 240V circuit draws 15A. What is the power consumed in watts?

Accepted Answer

3,600 W

Answer

P = V × I = 240 × 15 = 3,600 W.

Question 2

Using Ohm's Law, what is the current through a 48Ω resistor connected to a 120V source?

Accepted Answer

2.5 A

Answer

I = V / R = 120 / 48 = 2.5 A.

Question 3

What is the resistance of a device that draws 4A from a 240V source?

Accepted Answer

60 Ω

Answer

R = V / I = 240 / 4 = 60 Ω.

Question 4

A motor operates at 480V and 20A with a power factor of 0.85. What is the true (real) power in watts?

Accepted Answer

8,160 W

Answer

P = V × I × PF = 480 × 20 × 0.85 = 8,160 W.

Question 5

Three resistors of 10Ω, 20Ω, and 30Ω are connected in series. What is the total resistance?

Accepted Answer

60 Ω

Answer

In series, R_total = R1 + R2 + R3 = 10 + 20 + 30 = 60 Ω.

Journeyman Electrician’s Exam Practice Test