Contractor School Online ®
The premiere national online resource to assist you in passing your Contractor License Exam.

Tell a friend!

Email or Call (800)966-9596
Home  |  National Contractor License  |  Request Information  |  Construction Glossary  |  Login

Nebraska-Electrical Online Practice Test

These are actual questions from our online practice test.

We have included a question from each chapter of the test. Every question will be multiple choice. The answers are not included with the sample.

Sample Questions

# Chapter Title Question
1 Electrical, Connections, Panel Boards and Grounding What clearance is required for the front of a 208/120 panel?
2 Electrical, Heaters, Conductors, Bonding and Voltage 120/240 V single phase system with single black-red-white conductors (installed in single conduit) select "single set of conductors", 120/208 V 3 phase system with 2 conductors per phase and neutral (installed in 2 parallel conduits) select _________ conductors per phase in parallel", dc system with 3 positive and 3 negative conductors select "3 conductors per phase in parallel".
3 Electrical Branch Circuits Dual Element Fuse =
4 Electrical, Wires, Cables and Raceways For most 120/240V systems using cables of adequate ampacity, voltage drop is not a concern unless cable lengths are well over a hundred feet.
5 Motor Controls and Occupancies The smallest bonding conductor permitted for pool equipment is No.  ___ AWG.
6 NEC and Electrical Equipment

If a 60 gallon water heater has a name plate rating of 4500 watts and is fed by a 2 wire, 240 volt circuit, what is the minimum size NM cable conductors that can be used?

7 Electrical Transmission Lines and Communication Lines A messenger that is effectively grounded throughout its length will have the same clearance from the communications facilities that are required for a neutral conductor meeting regarding Rule ___________ in reference to fiber optic supply.
8 Electric Power Conditioning and Mechanical Electrical Lamp pole for exterior use is located 20 ft. away from the building. What type of raceway would be used?
9 Conduits, Voltmeters, Ammeter and Ohmmeter What color are the wire for pins 2 and 5 on an RJ13 jack?
10 Protected Premises, Fire Alarm Systems and Fundamentals

Every low power radio transmitter will automatically repeat alarm transmission at intervals not exceeding __ seconds until the initiating device is returned to its normal alarm condition.

11 Alarm Inspections, Testing and Maintenance How often shall detectors be tested?
12 Emergency Alarm Communication Systems, Control Functions and Interfaces What do smoke detectors mounted in the air ducts of HVAC systems do?
13 Electrical Miscellaneous, Conductors, Wires, Panels, EMT and Currents The maximum secondary conductor length permitted by the NEC from a transformer to a main breaker in an office building is _________ ft. The rules in Sec. 240.4 require you to protect all conductors against over current in accordance with their ampacities as specified in Sec. 310.15.
14 Photovoltaics The _____________ is the creation of voltage or electric current in a material upon exposure to light. The effect is directly related to the photoelectric effect, though they are different processes. When the sunlight or any other light is incident upon a material surface, the electrons present in the valence band absorb energy and, being excited, jump to the conduction band and become free.
15 Low Voltage Wiring UBC requirements for residential buildings limit openings betweem balustrades to less than ________ inches.
16 Electrical Systems, Cables, Wires and Electrical Sign Installation

A sign can be used as a pull box or junction box for adjacent signs, outline lighting systems, or floodlights that ______________..

17 Part 1 - Fluorescent, LED, HID Fabrication, Tubes and Electrical Flow


This technique uses a combination filamentcathode at each end of the lamp in conjunction with a mechanical or automatic (bi-metallic) switch  that initially connect the filaments in series with the ballast to preheat them; when the arc is struck the filaments are disconnected.


18 Part 2 - Fluorescent, LED, HID Fabrication, Tubes and Electrical Flow

In a discharging battery or a galvanic cell, the cathode is the positive terminal since that is where the current flows out of the device (see drawing). This outward current is carried internally by positive ions moving from the electrolyte to the positive cathode (chemical energy is responsible for this "____________" motion). 


19 Sign Components

 The voltage and current ratio of autotransformers can be formulated the same as other two-winding transformers:

frac{V_1}{V_2}=frac{N_1}{N_2} = a


The ampere-turns provided by the upper half:

F_U = (N_1 - N_2)I_1 = (1-frac{1}{a})N_1I_1

The ampere-turns provided by the lower half:

F_L = N_2(I_2 - I_1) = frac{N_1}{a}(I_2-I_1)

For ampere-turn balance, FU=FL:

(1-frac{1}{a})N_1 I_1 = frac{N_1}{a}(I_2-I_1)


frac{I_1}{I_2} = frac{1}{a}

20 Sign Design and Mounting

Programmable electronic signs shall be located in a manner that the director determines based on reasonable evidence will not adversely interfere with the visibility or functioning of traffic signals and traffic signage, taking into consideration the physical elements of the sign and the surrounding area, such as information analyzing physical obstruction issues, line of sight issues, brightness issues and visual obstruction or impairment issues, but not including the message content on the sign.

21 OSHA, Safety, Dig Alert, Asbestos and Code of Federal Regulations, Title 29, Part 1926

If an emergency notice must be given to Diggers Hot Line of Nebraska 811or 800-331-5666 Dig Alert, utility company will attempt to respond within _______.

22 Employees, Contractors, Insurance and Safety and Fire Extinguishers On a jobsite, you have to have a fire extinguisher for safety purpose within:
23 Mathematics and Calculations

If the voltage V in an electric circuit is held constant, the current I is inversely proportional to the resistance R. If the current is 50 amperes when resistance is 240 ohms,find current when the resistance is 150 ohms.

Go Back
What We Offer  |  Obtaining a Trade License  |  Test Preparation  |  About Us  |  Contact Us

Copyright © 1998-2019, Contractor School Online®,All Rights Reserved