Energy And Electricity Emma Flashcards
How are humans able to store energy?
Humans are able to take the energy from the sun and store it in a cell or battery.
This energy can then be used when needed
What are cells and batteries
A cell is the smallest whole part of a battery
A battery is a group of cells
How do cells and batteries store energy?
They store energy in the form of electricity
Where do we use batteries?
Cars Radios Torches Drills Cell phones Clocks Laptops Lots more
What is inside a battery?
A battery is full of chemicals which make electrical energy
What are the 2 ends of a battery called?
They are called terminals.
One end of the cell is positive and the other is negative
+ positive
- negative
How does energy move in the battery?
The chemicals in a cell give off electrical energy. This energy flows from the negative terminal to the positive terminal very quickly.
What is a circuit?
A circuit is a system that transfers electrical energy to where it is needed.
What is a system made up of?
Give 2 examples
It is made up of 2 or more parts. These pets work together to do useful things.
A pestle and mortar work together to grind spices, seeds and nuts
A can opener has many parts that work together to grip, turn and cut into a can. This allows us to open cans
What is an electrical system?
An electrical system is called a circuit
What does a simple circuit consist of?
A battery
Electrical wire
Light bulb
Light bulb holder
Explain how a simple electrical circuit works
When connected together the parts make an electrical circuit and the light bulb will shine.
How does electrical energy move?
Very quickly. It flows in the following ways:
- Starts at the negative terminal and flows to the positive terminal
- from the positive terminal it flows through the wire
- from the wire it flows through the light bulb and the bulb lights up
- from the light bulb the energy flows through the wire back to the negative terminal
When will the bulb stop shining?
When the energy is used up or the circuit is broken
What is a closed circuit
When the circuit is connected and the bulb is shining the circuit is a closed circuit
What is an open circuit
When there is a break in the circuit it is an open circuit.
How do we use electricity safely?
Electricity is dangerous if we don’t use it properly. Electricity from a wall socket can kill someone. Our bodies are good conductors of electricity.
How do we know if there is a problem with an appliance?
If:
The controls do not work properly
Any part of the appliance is broken or missing
Parts are loose
How do we practise plug safety
Use SABS approved plugs
Use an adaptor, don’t overload wall sockets
Do not pull a plug out by the cord
Switch off the socket before pulling out the plug
Don’t put anything other than plugs into the wall socket
Cover unused sockets with safety plugs
How do we get electricity from power stations?
Electricity which is made at power stations travels through pylons, substations and electricity boxes in a giant circuit, to our homes. After an appliance has used electricity, it flows back to the National Grid.
What do power stations need to produce electricity?
They need a source of energy, or fuel
What do power stations in South Africa use to produce electricity?
Most of them use coal. South Africa has a lot of coal.
Coal fired power stations burn coal and energy (in the form of heat) is given off. This heat is used to make electricity.
What sources does South Africa use to produce electricity?
Hydro electric power from water Wind turbines from wind Nuclear power stations Gas turbines Solar panels
