HVAC Electric Review Questions and Answers Rated A
Resistance is? Opposition to current flow
An electron has? A negative charge
Impedance is? Opposition to alternating current flow
Current flow is? Electron flow in a circuit
The safety ground conductor is usually color coded? Green or bare.
Like charges? Repel each other
The symbol for current is? I
Any material that will readily release electrons is called? A conductor
Which of the following materials would be best suited for
Silicon
use as a semi-conductor?
How many watts of power are used by a heater operating
1200 watts
at 240 volts and drawing 5 amps?
Three defrost heaters, each 15 ohms are wired in parallel
to a 120 volt power supply. How many watts of power will 2880 Watts
be used?
What would be the result, if a 24 volt, 20-ohm low voltage
contactor coil were wired in series with a 24 volt, 200-0hm Only the control relay would operate.
control relay coil?
Fuses are sized by? Volts & Amps
Which of the following is generally considered to be within
the maximum allowable (plus or minus) supply voltage 5%
variation?
Capacitors are rated in? Microfarads & Volts
When testing a capacitor with an analog or digital ohm-
Measure low resistance then return to high reading
meter, the meter should?
The hot conductor
, HVAC Electric Review Questions and Answers Rated A
In electrical wiring, a black colored wire in an alternating
current circuit usually indicates?
Which of the following meters must use its internal power
Ohmmeter
to check a load or circuit?
One horsepower is equal to watts 746
What is the term used to describe the output side of a
Secondary side
transformer?
In a series circuit, the voltage drop across each resistance
Add up to equal the source voltage
(load) will?
Which of the following is equal to 100 milliamps? 0.10 amperes
A parallel circuit contains a 18 ohm and a 9 ohm resistor.
6 Ohms
The total resistance equal?
The total resistance of a parallel circuit will be? Less than the smallest resistance
The voltage drop across each resistor will be the same as
When resistors are wired in parallel the voltage will be?
the applied source voltage
Current flow will increase when voltage increases True or
True
False?
Which of the following is equal to 2.1KW? 2,1OO Watts
A capacitor analyzer is designed to read? The capacitance of a capacitor
Three 300 ohm resistors are wired in parallel. The total
100 ohms
resistance equals?
On an electronic oil safety switch what changes the pres-
Transducer
sure signal to electrical signal?
The electric meter on a house measures the
Wattage
. ......... passing through it
The correct formula for determining wattage in an electri-
E times I
cal circuit?
Resistance is? Opposition to current flow
An electron has? A negative charge
Impedance is? Opposition to alternating current flow
Current flow is? Electron flow in a circuit
The safety ground conductor is usually color coded? Green or bare.
Like charges? Repel each other
The symbol for current is? I
Any material that will readily release electrons is called? A conductor
Which of the following materials would be best suited for
Silicon
use as a semi-conductor?
How many watts of power are used by a heater operating
1200 watts
at 240 volts and drawing 5 amps?
Three defrost heaters, each 15 ohms are wired in parallel
to a 120 volt power supply. How many watts of power will 2880 Watts
be used?
What would be the result, if a 24 volt, 20-ohm low voltage
contactor coil were wired in series with a 24 volt, 200-0hm Only the control relay would operate.
control relay coil?
Fuses are sized by? Volts & Amps
Which of the following is generally considered to be within
the maximum allowable (plus or minus) supply voltage 5%
variation?
Capacitors are rated in? Microfarads & Volts
When testing a capacitor with an analog or digital ohm-
Measure low resistance then return to high reading
meter, the meter should?
The hot conductor
, HVAC Electric Review Questions and Answers Rated A
In electrical wiring, a black colored wire in an alternating
current circuit usually indicates?
Which of the following meters must use its internal power
Ohmmeter
to check a load or circuit?
One horsepower is equal to watts 746
What is the term used to describe the output side of a
Secondary side
transformer?
In a series circuit, the voltage drop across each resistance
Add up to equal the source voltage
(load) will?
Which of the following is equal to 100 milliamps? 0.10 amperes
A parallel circuit contains a 18 ohm and a 9 ohm resistor.
6 Ohms
The total resistance equal?
The total resistance of a parallel circuit will be? Less than the smallest resistance
The voltage drop across each resistor will be the same as
When resistors are wired in parallel the voltage will be?
the applied source voltage
Current flow will increase when voltage increases True or
True
False?
Which of the following is equal to 2.1KW? 2,1OO Watts
A capacitor analyzer is designed to read? The capacitance of a capacitor
Three 300 ohm resistors are wired in parallel. The total
100 ohms
resistance equals?
On an electronic oil safety switch what changes the pres-
Transducer
sure signal to electrical signal?
The electric meter on a house measures the
Wattage
. ......... passing through it
The correct formula for determining wattage in an electri-
E times I
cal circuit?
