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Question
State the reason why, in a three pin plug, the earth pin is longer and thicker than the other two.
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Solution
The live terminal of the three pin plug helps us to connect our appliance to the live (or high voltage wire) or the ‘mains’. The neutral terminal connects the other end of the appliance to the ‘ground potential’ wire of the ‘mains’. The ‘earth’ terminal helps us to connect the body of the appliance to a wire whose other end is burned deep in moist earth. This ‘earthing’ of the body of the appliance acts as a safety measure and saves the user from any unwarranted dangerous shocks.
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