Class 10 Science Magnetic effects of Electric Current: NCERT Solutions for Question 18
What is the function of an earth wire? Why is it necessary to earth metallic appliances?
Earth wire is a safety measure that prevents short circuits and shock. When a live wire touches the metallic case of an electric gadget, the electric current flows from the casing of the appliance to the earth through the copper wire. As the earth offers very low or almost no resistance to the flow of current, so large current passes through the copper wire instead of the human body. Due to this large current heat is produced in the circuit and hence the fuse in the circuit melts. So, the circuit is switched off automatically and the electric appliance is saved from burning and no electric shock to the human body.
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