2562068
Description
Quiz by giannini.chambers, updated more than 1 year ago
|
Created by giannini.chambers
about 9 years ago
|
|
Question 1
Question
An inductor of 300mH placed on a 60Hz network will have an inductive reactance of?
Answer
-
113Ω
-
100Ω
-
113097Ω
-
97Ω
Question 2
Question
A capacitor of 90µF is placed on an electrical network of frequency 65 Hz. What is the value of capacitive reactance?
Answer
-
27Ω
-
27000000Ω
-
27000Ω
-
0.0027Ω
Question 3
Question
What is the typical generation voltage at a power station?
Answer
-
25kV
-
125kV
-
11kV
-
33kV
Question 4
Question
Where is the neutral connected on the secondary of a delta to star transformer?
Answer
-
The end of every line
-
The star point of the transformer
-
To the middle of every winding
-
Left floating
Question 5
Question
What is the phase separation angle in a typical star system between phases?
Answer
-
100°
-
120°
-
360°
-
110°
Question 6
Question
A voltage of 700V is applied to two resistors in series. A current of 2.8A flows. If one of the resistors is 150Ω what is the value of the other?
Answer
-
100Ω
-
50Ω
-
75Ω
-
124Ω
Question 7
Question
What is the series impedance of a circuit where the resistance is 30Ω the inductive reactance is 70Ω and the capacitive reactance is 30Ω?
Answer
-
50Ω
-
65Ω
-
70Ω
-
40Ω
Question 8
Question
If you have a star phase voltage of 135V what would the line voltage be?
Answer
-
234V
-
200V
-
78V
-
75V
Question 9
Question
A 30kW lift motor is running at 0.95 power factor. Calculate the line current that is drawn from the supply when the voltage is 390V:
Answer
-
47A
-
40A
-
37A
-
50A
Question 10
Question
What type of light fitting requires no control gear?
Answer
-
Incandescent
-
Fluorescent
-
Sodium Discharge
-
High pressure mercury
Question 11
Question
Which type of protective device natively offers the functions of earth fault, residual current and short circuit protection?
Answer
-
RCBO
-
MCB
-
RCD
-
ACB
Question 12
Question
A light source of 300 Candela is placed 2.5m above a table. Calculate the illuminance at a point directly below the light fitting.
Answer
-
48 Lux
-
48 Lumens
-
120 Lux
-
120 Lumens
Question 13
Question
The full load current of a transformer is 650A and the voltage is 400V between phases. Calculate the apparent power rating of the transformer.
Answer
-
450kVA
-
400kVA
-
180kVA
-
400kW
Question 14
Question
In a TT system the means of earthing is provided by:
Answer
-
Distributor's earth supply
-
Installation earth electrode
-
Combined neutral and earth
-
None it is an earth free location
Question 15
Question
The phase voltage supplied to a building is 270V. The building is given a 3 phase 3 wire supply. What voltage are available to work with?
Answer
-
270V and 468V
-
468V
-
270V, 468V and 135V
-
300V
-
300V and 500V
Question 16
Question
Calculate the angle the current lags the voltage in a network where there is 30kW and 12kVAr on the network.
Answer
-
21.8°
-
18°
-
25°
-
26.7°
Question 17
Question
A centre tapped to earth transformer has a voltage of 75V phase to earth. What would the full voltage available be?
Answer
-
150V
-
100V
-
37.5V
-
130V
Question 18
Question
A 25kW load is being drawn from a supply at 350V. Calculate the power loss through the conductor if the resistance is measured at 0.3Ω.
Answer
-
1000W
-
1640W
-
1530W
-
2160W
Question 19
Question
The potential difference between a cat and the earth is 1000V. If the resistance of the cat is measured at 250Ω what would the current flow to earth be?
Answer
-
10A
-
250000A
-
4V
-
4A
Want to create your own Quizzes for free with GoConqr? Learn more.