Quiz_________________?
A 240V, 24A, single-phase load is located 160 ft from the panelboard. The load is wired with
10 AWG conductors. What's the approximate voltage drop of the branch-circuit
conductors?
a. 3.2V
b. 4.25V
c. 5.9V
d. 9.5V -
Answer✅
d. 9.5V
VD = (2 x K x I x D)/Cmil
K = 12.90, copper
I = 24A
D = 160 ft
Cmil = 10,380
VD = (2 wires x 12.90 x 24A x 160 ft)/10,380 cmil
VD = 9.50V
Quiz_________________?
1
,During normal operation of a typical 120-volt appliance circuit, current flows through the
hot, grounding, and neutral conductors.
a. True
b. False -
Answer✅
b. False
Quiz_________________?
An RLC series circuit has an applied voltage of 240 volts. R = 48 Ω, XL = 100 Ω, XC = 36 Ω,
and Z = 80 Ω. What is the total current?
a. 1 A
b. 2 A
c. 3 A
d. 4 A -
Answer✅
c. 3 A
240/80 = 3
Quiz_________________?
What's the direct-current resistance of a 6 AWG copper conductor that's 400 ft long?
a. 0.20 ohms
b. 0.30 ohms
c. 0.40 ohms
d. 0.50 ohms -
Answer✅
2
,a. 0.20 ohms
6 AWG resistance = 0.491 ohms/1,000 ft [Chapter 9, Table 8]
(0.491 ohms/1,000 ft) x 400 ft = 0.1964 ohms
Quiz_________________?
What is the monthly cost of operating a 240V, 5kW central electric heater that operates 12
hours per day when the cost is 15 cents per kilowatt-hour (kWhr)?
a. $ 270
b. $ 87
c. $ 390
d. $ 313 -
Answer✅
a. $ 270
2020 Ugly's Pg. 117
Cost = Watts x hours used x rate per kWhr/1000
(5000 x 360 x 0.15) / 1000 = 270
Quiz_________________?
A 100 Watt incandescent lamp is to be replaced with a 15 Watt, LED equivalent. If the cost
per kWhr is 15 cents, how many hours would the new lamp need to operate to pay for
itself? Lamp cost is $4. Energy saved is 85 Watts.
a. 1307 Hours
b. 9 Hours
c. 314 Hours
d. 173 Hours -
3
, Answer✅
c. 314 Hours
2020 Ugly's Pg. 117
Hours = Lamp cost x 1000 / Watts saved x kWhr
(4 x 1000) / (85 x 0.15) = 313.73
Quiz_________________?
An inductor with an inductance of three henrys (H) is to be connected to a 60 Hz circuit.
What will the inductive reactance be?
a. 180 Ω
b. 360 Ω
c. 565 Ω
d. 1131 Ω -
Answer✅
d. 1131 Ω
Xl = 2 x 3.1416 x Frequency x Inductance
2 x 3.1416 x 60 x 3 = 1130.98 ohms
Quiz_________________?
An electric motor is running on 120 V. The current is measured to be 2 A. How many ohms
of resistance is the motor?
a. 60
b. 118
c. 122
d. 240 -
4
A 240V, 24A, single-phase load is located 160 ft from the panelboard. The load is wired with
10 AWG conductors. What's the approximate voltage drop of the branch-circuit
conductors?
a. 3.2V
b. 4.25V
c. 5.9V
d. 9.5V -
Answer✅
d. 9.5V
VD = (2 x K x I x D)/Cmil
K = 12.90, copper
I = 24A
D = 160 ft
Cmil = 10,380
VD = (2 wires x 12.90 x 24A x 160 ft)/10,380 cmil
VD = 9.50V
Quiz_________________?
1
,During normal operation of a typical 120-volt appliance circuit, current flows through the
hot, grounding, and neutral conductors.
a. True
b. False -
Answer✅
b. False
Quiz_________________?
An RLC series circuit has an applied voltage of 240 volts. R = 48 Ω, XL = 100 Ω, XC = 36 Ω,
and Z = 80 Ω. What is the total current?
a. 1 A
b. 2 A
c. 3 A
d. 4 A -
Answer✅
c. 3 A
240/80 = 3
Quiz_________________?
What's the direct-current resistance of a 6 AWG copper conductor that's 400 ft long?
a. 0.20 ohms
b. 0.30 ohms
c. 0.40 ohms
d. 0.50 ohms -
Answer✅
2
,a. 0.20 ohms
6 AWG resistance = 0.491 ohms/1,000 ft [Chapter 9, Table 8]
(0.491 ohms/1,000 ft) x 400 ft = 0.1964 ohms
Quiz_________________?
What is the monthly cost of operating a 240V, 5kW central electric heater that operates 12
hours per day when the cost is 15 cents per kilowatt-hour (kWhr)?
a. $ 270
b. $ 87
c. $ 390
d. $ 313 -
Answer✅
a. $ 270
2020 Ugly's Pg. 117
Cost = Watts x hours used x rate per kWhr/1000
(5000 x 360 x 0.15) / 1000 = 270
Quiz_________________?
A 100 Watt incandescent lamp is to be replaced with a 15 Watt, LED equivalent. If the cost
per kWhr is 15 cents, how many hours would the new lamp need to operate to pay for
itself? Lamp cost is $4. Energy saved is 85 Watts.
a. 1307 Hours
b. 9 Hours
c. 314 Hours
d. 173 Hours -
3
, Answer✅
c. 314 Hours
2020 Ugly's Pg. 117
Hours = Lamp cost x 1000 / Watts saved x kWhr
(4 x 1000) / (85 x 0.15) = 313.73
Quiz_________________?
An inductor with an inductance of three henrys (H) is to be connected to a 60 Hz circuit.
What will the inductive reactance be?
a. 180 Ω
b. 360 Ω
c. 565 Ω
d. 1131 Ω -
Answer✅
d. 1131 Ω
Xl = 2 x 3.1416 x Frequency x Inductance
2 x 3.1416 x 60 x 3 = 1130.98 ohms
Quiz_________________?
An electric motor is running on 120 V. The current is measured to be 2 A. How many ohms
of resistance is the motor?
a. 60
b. 118
c. 122
d. 240 -
4
