Chapter 6 Generation Of Electricity Flashcards
What are the 2 main electricity groups?
Renewable energy sources and non-renewable energy sources
Definition of renewable energy sources?
Energy sources that can be replaced continually and will never deplete
Definition of non-renewable energy sources?
Energy sources that cannot be replaced and will deplete
Examples of renewable energy sources
Hydro
Wave
Solar
Tidal
Wind
Biomass
Geothermal
Examples of non renewable energy sources
Nuclear
Coal
Natural Gas
Petroleum
What is a generator?
Device used to generate electricity
What is electricity current produced by?
Movement of the wire and movement of the magnet
Types of electric current?
Alternating current and direct current
What is a direct current?
Current the flows in 1 direction only
What is an alternating current
Current that flows in constantly reversing directions
Examples of devices and sources of direct current
Flashlight, calculator, solar cells, batteries
Examples of devices using alternating current
Hair dryer. air conditioner, bread toaster
What the fuck is a Cathode Ray Oscilloscope
Electric device used to show the differences in the shape of graph, direction of current and voltage change
What is a transformer?
Device for changing the voltage of an alternating current
What is a transformer made up of?
Laminated soft iron core and 2 insulated coils
Types of transformers?
Step up transformers and step down transformers
Explain about the step-up transformer
The primary voltage across the primary coil is lower than the secondary voltage across the secondary coil because the primary coil has less turns than the secondary coil
Explain about the step down transformer
Primary voltage across the primary coil is higher than the secondary voltage across the secondary coil because the number of turns on the primary coil is more than the secondary coil
What is the supplied voltage of alternating current in malaysia?
240V
Examples of electrical appliance that operates at 240v alternating current without a transformer
Electrical stove, heater
Compare the ratio of the primary voltage to the secondary voltage and the number of turns of the primary coil to the secondary coil in a transformer
The ratio of the primary voltage to the secondary voltage is equal to the ratio of the number of turns of the primary coil to the number of turns of the secondary coil in a transformer
Transmission tree of electricity
Power station > Step-up transformer > National Grid Network > Main substation ( switch zone/step-down transformer ) > Heavy industrial area/light industrial area/residential areas
Amount of volts needed for heavy, light industrial areas and residential areas/offices
Heavy- 33 kV
Light - 11 kV
Office/Residential areas - 240 V
Impact on residencies located near national grid network pylons?
If strong enough cause short term health effects such as dizziness and disrupts the position of the compass needle`
Types of electrical wiring system?
Single-phase wiring/three phase wiring
Limitations of single-phase wiring
Suitable and stable enough for electricity usage not exceeding 10 kW or 50A
- Rural residential areas
Limitations of three-phase wiring
Used in industrial/commercial areas where electricity usage is over 10 kW or 50 A
Types of plugs
3-pin / 2-pin plugs
Examples of appliances using 3-pin plugs
Electrical kettles
Irons
Example of appliances using 2-pin plugs
Hair dryer
Electric toothbrush
Colour of earth, neutral and live wire
Earth- Yellow and greens striped
Neutral - Blue
Live - Brown
Safety components in the wiring system of a house
Earth Leakage Circuit breaker
Switch
Earth Wire
Miniature circuit breaker
3 A, 5 A, 10 A and 13 A fuses
What is a fuse?
A fine and short wire that heats up easily and melts when current flowing through exceeds the value of the fuse. If the wire of the fuse melts, the electricity supply cuts off
Types of fuses
Cartridge fuses and replaceable wire fuses
What is the function of a fuse?
as an electrical safety device, to prevent excessive current flow
Types of fuse ratings
1, 2, 3, 5, 10, 13, 15, 30 A
What is the importance of safety in the use of electrical appliances? Why?
To protect us because the ratio of deaths due to injury of electrical accidents is high compared to other categories of accidents
What is the meaning of energy efficiency
It is the percentage of energy input converted to useful form of energy output
What is the formula for energy efficiency?
Useful energy output/Energy input supplied x 100%
Examples of technology which applies the concept of energy efficiency?
LED Bulbs and electric vehicles
Examples of light bulbs
Filament Lamp, Energy saving lamp and LED lamp
What is the function of an electric meter?
Measure the quantity of electricity used to determine the cost of electricity consumed
What is the meaning of electric power?
rate of electrical energy used by an electric device
What is the meaning of electric current
The rate of flow of electric charge through a conductor
Definition of voltage
Electrical energy used to move a unit of electric charge
What are ways to save electrical energy consumption
Construct green buildings
Use energy-efficient appliances
Features of a green building
Efficient ventilation system to reduce the use of air conditioning
Maximising the used of natural lighting to reduce the cost of electrical energy consumption
