TCM 322 FINAL EXAM QUESTIONS
AND ANSWERS ALL CORRECT
Why is the majority of power produced and consumed in the United Stated alternating
current? - Answer- Smaller transmission conductors, lower generation costs, easier
voltage transformations (all of the above)
What is the cross sectional area in square inches for a #10 THWN conductor? -
Answer- 0.0211
Which of the following is the correct formula for ohm's law - Answer- E= I x R
In building construction and power distribution, a transformer is generally used for: -
Answer- changing voltage in the conductor
What is the working (or true) power being consumed by a 240-volt, single phase AC
motor (PF= of .91) that draws 7.5 amps? - Answer- 1638 watts
Rate of flow of electric charge - Answer- current
The ability to store energy in an electric field - Answer- capacitance
The relationship between the apparent power and true power for utilization equipment -
Answer- power factor
Measure of electromotive potential - Answer- voltage
A measure of resistance to AC circuits comprised of both resistance and reactance -
Answer- impedance
Incandescent lamps have been used for over 125 years, which of the following is NOT
an advantage of using lamps based upon Edison's original idea from 1879? - Answer-
Resistance to voltage variation
Which of the following is an important performance criterion for ballasts? - Answer-
Heat, noise, dimming control (all of the above)
, Which of the following ballasts types are considered to be antiquated or out-of-date
technology? - Answer- Magnetic
Which of the following is a type of high intensity discharge (HID) lamp? - Answer-
Mercury lamps, Metal halide lamps
The purpose of lighting is to provide for: - Answer- Flexibility, reduce energy usage
Which of the following is NOT an enclosure type you can find specified for a motor? -
Answer- liquid-immersed/self-air cooled
Halogen lamps use a tungsten filament that evaporates when heated by current. Light is
generated when the tungsten evaporates. - Answer- true
Modern electronic ballasts can be dimmed over the full range of light outputs - Answer-
true
Fluorescent lamps emit visible light from the arc of the electricity between the electrodes
in each tube end - Answer- false
static control schemes for lighting incorporate feedback through occupancy sensors and
illumination level sensors to adjust the lighting levels - Answer- false
what is the correct term for a "light bulb" (e.g, a 60-watt GE incandescent as pictured
below) - Answer- lamp
Type of "light-bulb" that requires no ballast; it provides excellent color rendering -
Answer- halogen
considered a low intensity discharge lamp; utilizes a phosphorus coated tube - Answer-
fluorescent
type of "light-bulb" that provides the highest efficiency of virtually any light source -
Answer- low pressure sodium
luminous power per unit area ( 1 lumen per sq. ft.) - Answer- illuminance
ratio of lumens produced by a lamp to the watts consumed - Answer- efficacy
what is the total estimated electrical load (lighting and outlets only) for a 6000ft^2 church
that has 20 convenience receptacles?
21,00V-A
12,000V-A
9600V-A
8400V-A
none of the above - Answer- none of the above
AND ANSWERS ALL CORRECT
Why is the majority of power produced and consumed in the United Stated alternating
current? - Answer- Smaller transmission conductors, lower generation costs, easier
voltage transformations (all of the above)
What is the cross sectional area in square inches for a #10 THWN conductor? -
Answer- 0.0211
Which of the following is the correct formula for ohm's law - Answer- E= I x R
In building construction and power distribution, a transformer is generally used for: -
Answer- changing voltage in the conductor
What is the working (or true) power being consumed by a 240-volt, single phase AC
motor (PF= of .91) that draws 7.5 amps? - Answer- 1638 watts
Rate of flow of electric charge - Answer- current
The ability to store energy in an electric field - Answer- capacitance
The relationship between the apparent power and true power for utilization equipment -
Answer- power factor
Measure of electromotive potential - Answer- voltage
A measure of resistance to AC circuits comprised of both resistance and reactance -
Answer- impedance
Incandescent lamps have been used for over 125 years, which of the following is NOT
an advantage of using lamps based upon Edison's original idea from 1879? - Answer-
Resistance to voltage variation
Which of the following is an important performance criterion for ballasts? - Answer-
Heat, noise, dimming control (all of the above)
, Which of the following ballasts types are considered to be antiquated or out-of-date
technology? - Answer- Magnetic
Which of the following is a type of high intensity discharge (HID) lamp? - Answer-
Mercury lamps, Metal halide lamps
The purpose of lighting is to provide for: - Answer- Flexibility, reduce energy usage
Which of the following is NOT an enclosure type you can find specified for a motor? -
Answer- liquid-immersed/self-air cooled
Halogen lamps use a tungsten filament that evaporates when heated by current. Light is
generated when the tungsten evaporates. - Answer- true
Modern electronic ballasts can be dimmed over the full range of light outputs - Answer-
true
Fluorescent lamps emit visible light from the arc of the electricity between the electrodes
in each tube end - Answer- false
static control schemes for lighting incorporate feedback through occupancy sensors and
illumination level sensors to adjust the lighting levels - Answer- false
what is the correct term for a "light bulb" (e.g, a 60-watt GE incandescent as pictured
below) - Answer- lamp
Type of "light-bulb" that requires no ballast; it provides excellent color rendering -
Answer- halogen
considered a low intensity discharge lamp; utilizes a phosphorus coated tube - Answer-
fluorescent
type of "light-bulb" that provides the highest efficiency of virtually any light source -
Answer- low pressure sodium
luminous power per unit area ( 1 lumen per sq. ft.) - Answer- illuminance
ratio of lumens produced by a lamp to the watts consumed - Answer- efficacy
what is the total estimated electrical load (lighting and outlets only) for a 6000ft^2 church
that has 20 convenience receptacles?
21,00V-A
12,000V-A
9600V-A
8400V-A
none of the above - Answer- none of the above
