Electrical safety at home
Describe the graph on your companion sheet.
The graph shows 2 sets of data on 1 set of axis, and
Describe is a key word meaning "say what you see" rather than to explain what your seeing.
Watch the video and answer the questions on the companion sheet.
What are these objects?
What are they called?
What is their purpose?
How do they achieve their purpose?
Where would you find them at home?
Lets have a look at this electric cooker.
The cooker has a metal outer case.
Without the earth wire, if a fault occurs and the live wire becomes loose, there is a danger that it will touch the case. The next person who uses the appliance could get electrocuted.
The earth wire is therefore connected to the case and is attached to a metal plate or water pipe underground. As the wire is made of copper, the earth wire provides a low resistance path to the ground. In the event of a fault, the large live current passing through the case earth wire will follow this path to the ground instead of passing through a person, and will blow the fuse rendering the appliance safe.
In your own words, describe the role of the earth wire on your companion sheet
Watch the video and then click the link and use the internet to research the 3 pin plug.
Complete the table
Click the link to find out more about circuit breakers, then answer the questino son the companion sheet.
Fuses work on the principal of a large current melting the fuse wire. In some cases faults can occur in which the current may not be large enough to melt the fuse but enough to seriously harm the user of the electrical appliance. For protection against faults of this nature a circuit-breaker is used in place of a fuse.