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Missouri-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, 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.
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, Connections, Panel Boards and Grounding What clearance is required for the front of a 208/120 panel?
4 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 ______________..

5 Electrical Branch Circuits Dual Element Fuse =
6 Motor Controls and Occupancies The smallest bonding conductor permitted for pool equipment is No.  ___ AWG.
7 NEC and Electrical Materials

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?

8 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.
9 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?
10 Conduits, Voltmeters, Ammeter and Ohmmeter What color are the wire for pins 2 and 5 on an RJ13 jack?
11 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.

12 Alarm Inspections, Testing and Maintenance How often shall detectors be tested?
13 Emergency Alarm Communication Systems, Control Functions and Interfaces What do smoke detectors mounted in the air ducts of HVAC systems do?
14 Sensors, Devises, Controls and Conductors By using a combination of magnetic contacts and _________________, a glass door with a glass transom may be protected.
15 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.
16 Computers, Satellite Dish, Transmission Systems and Communication Circuits All TV satellites rotate in the _____ orbit.
17 Telecommunications Cross Talk A delay line based on the time of propagation of electromagnetic waves is considered to be an _________________________.
18 Cable and Phone Installation Systems

A _____________ is a network that covers a broad area (i.e., any telecommunications network that links across metropolitan, regional, or national boundaries) using private or public network transports.

19 Topology, Cable Specification and Telecommunications _________________ is the mathematical study of shapes and spaces. It is a major area of mathematics concerned with the most basic properties of space, such as connectedness, continuity and boundary. It is the study of properties that are preserved under continuous deformations including stretching and bending, but not tearing or gluing.
20 Electrical Signs and 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}

21 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.

22 Sign Troubleshooting and Repair

The thermoplastic used to mold many common cheap connectors softens or melts at relatively low temperatures. This can result in the pins popping out or shifting position (even shorting) as you attempt to solder to them to replace a bad connection. One approach that works in some cases is to use the _____________ socket to stabilize the pins so they remain in position as you solder. The plastic will still melt - not as much if you use an adequately sized iron since the socket will act as a heat sink - but will not move.

23 Safety Electrical and Grounding Signs

Portable or mobile signs must be adequately supported and readily movable without the use of tools . Each portable or mobile sign must have an attachment plug. Remember that 400.8(2) and (5) prohibit flexible cords from being run through (or above) a suspended ____________.

24 OSHA Safety, Dig Alert, Fire Extinguishers, Asbestos and Code of Federal Regulations, Title 29, Part 1926

If an emergency notice must be given to Ohio Utilities Protection Service 811 Dig Alert, the utility company, will attempt to respond within _______.

25 Mathematics, Calculations and Formulas

 The voltage of E of an alternating current electrical circuit can be represented by the sinusoidal function E=220cos(pi t) where E is measured in volts and t is measured in seconds. how long does it take the alternating current to complete one cycle?

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