WorksheetsEnergy Sources and Power Systems Quiz
Total questions: 30
Worksheet time: 15mins
Which of the following is a non-renewable energy source?
Solar energy
Wind energy
Coal
Hydroelectric power
Which of the following is a renewable source of energy?
Diesel
Natural Gas
Wind
Nuclear
What does magnetism refer to?
The force that acts between magnets and magnetic materials
The force that acts between electric charges
The force that acts between gravitational bodies
The force that acts between chemical compounds
The following are among the parts of power system except
Generation
Fuse
Transmission
Distribution
The following are found in Hydroelectric generating plant except
Dam
Turbine
Generator
Boiler
What is the role of a step-down transformer in the power distribution system?
To increase the voltage for long-distance transmission
To generate electricity
To decrease the voltage for safe home usage
To store electricity
Electrical machine that converts mechanical energy into electrical energy is called a Generator
True
False
Load curves in power system are grouped into two, these are
Mechanical and magnetic
Base and peak load
Heat and light loads
In which direction does the magnetic field flow externally to the magnet?
From south (S) to north (N)
From east (E) to west (W)
From north (N) to south (S)
From west (W) to east (E)
What is the symbol for magnetic flux?
Φ (phi)
γ (gamma)
β (beta)
α (alpha)
What is the term used to describe the flow of magnetic field lines through a given area?
Electric Flux
Magnetic Field
Electric Field
Magnetic Flux
The high voltage transmission method is designed to:
Standardise plant manufacture design of gear
Produce high current in the lines
Maintain distribution voltage at the statutory values
Reduce the electrical losses in then lines
The main advantage of an overhead system as compared with an underground system is that overhead lines:
Cheaper to construct
Have fewer faults per mile
Can go across the country
Require less maintenance
The transitional voltage levels from the 66 kV to the towns are
66kV/28kV, 28kV/33kV, 33kV/415V
66kV/33kV, 33kV/11kV, 11kV/415V
66kV/11kV, 11kV/33kV, 33kV/240V
66kV/10kV, 10kV/6kV, 6kV/400V
Auto-reclose types of switchgear are installed
As generator switches for the purpose of synchronising
To keep on reclosing by an engineer
To improve continuity of supply on systems
To reclose when opened by an operator
The abbreviation PME used in the earthing of supply system refers to
Protective multiple earth
Potential multiple earth
Premium Main earth
Portable main earth
In an earthing system, SNE stands for which one of the following?
Single Node and Earth
Single Node Earth
Separate Neutral and earth
Separate node and earth
A conservator tank on a power transformer is fitted
To assist in the cooling of the oil
As it is necessary to have a specific quantity of oil in the transformer
To provide for differences in oil volume at varying temperatures
To protect the oil against emulsification
A competent person is
Trained, experienced and qualified
Trained, experienced and over 25
Qualified, experienced and over 25
Trained, inexperienced and qualified
Faults in underground installations of cable networks may be caused by
High resistance between phases
High capacitance between phases
Low resistance between phase and earth
High capacitance between phase and earth
Generating stations are inter-connected in order to
Control the load
Transfer power between consumers
Reduce the voltage drop in overhead lines
Reduce I2 R losses
Ideally, what property do inductors have?
Resistance
Capacitance
Inductance
Conductance
What principle do transformers rely on?
Electromagnetic radiation
Mutual induction
Static electricity
Thermal conduction
What happens when an AC current is applied to a coil in a transformer?
A changing magnetic field is produced
A static electric field is produced
Heat is generated
Light is emitted
What happens when a magnet is moved through a coil of wire?
It induces an electromotive force (voltage) in the coil
It generates heat in the coil
It creates a magnetic field around the coil
It produces light in the coil
Which of the following materials is commonly used as an insulator in electrical systems:
Copper
Aluminium
Iron
Rubber
Fuses are used to protect electrical plant and apparatus by acting as:
The weakest link for over-currents
A voltage sensitive link
A surge protector
A fault monitor
What is the function of a circuit breaker in an electrical system?
To provide a continuous power supply
To increase the voltage level
To automatically interrupt power flow during a fault
To convert AC to DC
What is the purpose of iron cores in transformers?
To increase the resistance between coils
To decrease the coupling between coils
To increase the coupling between coils by providing an easy path for magnetic flux
To provide insulation between coils
What are the two types of iron-core construction?
Laminated type and Non-laminated type
Core type and Shell type
Magnetic type and Non-magnetic type
Insulated type and Non-insulated type
