Term 3 Flashcards
What is an electric circuit used for?
The transfer of energy
State the three components all electric circuits have:
- A source of energy (cell/battery)
- Conductors (like copper wire)
- A device (Eg: motor/lightbulb/resistor)
Give 3 examples of sources of electrical energy:
Batteries
Generators
Wind turbines
Solar power
Dynamos
What is a switch used for? (Eg: light switch, kettle switch, the on button on the TV)
To break or continue electrical flow (open or close the circuit)
When electricity flows through a motor, what is the energy converted into?
Electrical energy —> Kinetic energy
When electricity is supplied to a device, the device converts it into a different form of energy. For a lightbulb electricity is turned into light energy, for a heater it is converted into heat energy
What materials are conductors often made of?
Metals, especially copper
What is the difference between a conductor and non-conductor, and name an example of a non-conductor:
Non-conductors do not allow electrical flow
Eg; Wood, plastic, cotton, etc.
State two ways that electricity is important for the economy:
- it powers electrical machines. this is useful in both industrial and agricultural businesses
- keeping power plants running requires people, thus creates jobs
- it keeps us connected to the internet, which is important for many if not all modern corporate jobs.
Why is coal relatively inexpensive in South Africa? And what is it used for?
South Africa has large coal deposits, making it abundant and easily accessible. It is mainly used to fuel power stations.
Why is coal relatively inexpensive in South Africa? And what is it used for?
South Africa has large coal deposits, making it abundant and easily accessible. It is mainly used to fuel power stations.
How does coal create energy in a power plant?
1.) The coal is burned
2.) Steam turns a turbine
3.) The generator coil is turned
4.) Electricity is generated
What infrastructure is needed to keep electricity running? (6 things)
Coal mines
Transport
Substations
Wiring
Power stations
Cables
Why is electricity expensive?
Keeping the infrastructure functional requires workers salaries to be paid, material costs to build and maintain the infrastructure and money to transport the materials
State 4 ways to save electricity
Use energy saving light bulbs
Install solar panels
Turn off devices and plugs not in use
Make use of natural light during the day time
Wear warmer clothes instead of putting on heaters
Dont overuse appliances
What causes do illegal connections have?
Traffic lights stop working
Vital services such as hospitals are left without electricity
Economic losses when freezers dont work and food rots
Increased prices to cover losses
Open wires can hurt people
