cameroon gce A level 2024 design of electrical installation 1

1. The distribution system which is more reliable Service Mains
is
A Radial system
B Tree system
C Ring main system
D All are equally reliable
Ring Main
Seders Distributors
SUB
2. The symbol of figure 1 represents RMD STATION
Feeders
Distributors
Figure 1
A Hydro electric power station
B Nuclear power station
C Thermal power station
D Windy power station
Figure 3
A Substation
B Ring distribution system
C Radial distribution system
D Receiving station
3. One advantage of a metallic conduit is
A Provide protection against mechanical
damage
B Provide protection against electric shock
C Provide protection against magnetic
leakage
D Provide protection against chemical
reaction
9. Light rays are generally classified as shown in the
diagram of figure 4
Wavelength in nano meter
0.00011
Cosmic Rays
Y Rays
X Rays
Ultra violet
0.001 +
0.1 4
4. The power plant which is the most reliable is
A Wind power plant
B Steam power plant
C Hydro power plant
D Nuclear power plant
380 T
Violet
10 + 45Q+–Blue
500—

5. In a semi direct lighting system the percentage of light directed to the working surface is:
A 40–60
B 60–80
C 90–100
D 60–90
Low Frequency 759!
Figure 4
The range of the wavelength in nano meter of X-rays
6. Figure 2 represents 6 multi-core cables of is between
A 0.1 To 10
B 380 to 450
C
.
610 to 760
Figure 2 D 760 to 4x 10
A 2 layers of 3 touching cables
B 2 layers of 4 touching cables
C 2 layers of 6 touching cables
D 2 layers of 7 touching cables
5
10. The formula to calculate the number of poles
required in low voltage line distribution is
A Length/Span +1
B • Length/Span – 1
C Span/Length +1
D Span/Length –1
7.In an electrical installation, the phase conductor
is 35mm2. The value of the PE is
A 20mm2
• B 35mm2
C 16mm2
D 10mm