HVAC Excellence - ELECTRICITY Exam
Questions And Correct Answers
Current flow is: - answer✔✔The flow of electrons in the circuit.
Impedance is: - answer✔✔Opposition to alternating current flow.
Like charges; - answer✔✔repel each other.
Any material that will readily release electrons is called; - answer✔✔A conductor
The symbol for current is; - answer✔✔I
Which of the following materials would be best suited for use as a semi-conductor? -
answer✔✔silicon
The safety ground conductor is usually color coded; - answer✔✔green or bare.
An electron has; - answer✔✔a negative charge.
Resistance is: - answer✔✔Opposition to current flow.
How many watts of power are used by a heater operating at 240 volts and drawing 5 amps? -
answer✔✔1200 watts
Which of the following meters must use its internal power to check a load or circuit? -
answer✔✔Ohmmeter
In electrical wiring, a black colored wire in an alternating current circuit usually indicates; -
answer✔✔the hot conductor.
Fuses are sized by: - answer✔✔Volts & Amps
What would be the result, if a 24 volt, 20-ohm low voltage conta ctor coil were wired in series
with a 24 volt, 200-ohm control relay coil? - answer✔✔Only the control relay would operate.
Three defrost heaters, each 15 ohms are wired in parallel to a 120 volt power supply. How many
watts of power will be used? - answer✔✔2880 Watts
Which of the following is generally considered to be within the maximum allowable (plus or
minus) supply voltage variation? - answer✔✔5%
Capacitors are rated in - answer✔✔Microfarads & Volts.
When testing a capacitor with an analog or digital ohmmeter, the meter should; -
answer✔✔measure low resistance then return to high reading.
What is the term used to describe the output side of a transformer? - answer✔✔Secondary side.
One horsepower is equal to __________ watts. - answer✔✔746
How much resistance must be placed in a 120 volt circuit in order to limit the current to 2 amps?
- answer✔✔60 Ohms
A parallel circuit contains a 18 ohm and a 9 ohm resistor. The total resistance equals; -
answer✔✔6 ohms.
In a series circuit, the voltage drop across each resistance (load) will. - answer✔✔add up to equal
the source voltage.
The total resistance of a parallel circuit will be; - answer✔✔less than the smallest resistance.
Which of the following statements about current is true? - answer✔✔Current flow will increase
when voltage increases.
When resistors are wired in parallel; - answer✔✔the voltage drop across each resistor will be the
same as the applied source
Which of the following is equal to 2.1KW? - answer✔✔2,100 Watts
Which of the following is equal to 100 milliamps? - answer✔✔0.10 amperes
A capacitor analyzer is designed to read; - answer✔✔the capacitive resistance of a capacitor.
On an electronic oil safety switch what changes the pressure singal to electrical signal? -
answer✔✔Transducer.
The electric meter on a house measures the ______________ passing th rough it. -
answer✔✔wattage
A three phase load requires a minimum of; - answer✔✔three supply lines.
Which of the following is the correct formula for determining wattage in an electrical circuit? -
answer✔✔W = E times I
A parallel circuit consists of three resistors.R1 = 30 Ohms, R2 = 15 Ohms, R3 = 10 Ohms. If the
current through R2 is 4 Amps (I = 4 Amps), what is the source Voltage? - answer✔✔60 volts
Three 300 ohm resistors are wired in parallel. The total resistance equals; - answer✔✔100 ohms
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