Which one of the following statements is not true?
(a) In a house circuit, lamps are used in parallel.
(b) Switches, fuses, and circuit breakers should be placed in the neutral wire
(c) An electric iron has its earth wire connected to the metal case to prevent the user receiving a shock
(d) When connecting a three-core cable to a 13 A three-pin plug, the red wire goes to the live pin.
(b) Switches, fuses and circuit breakers should be placed in the neutral wire.
Explanation
Switches, fuses and circuit breakers should be placed in the live wire, not in the neutral wire because if they would be connected to the neutral wire, then when excessive flowing of current will occurs they all burn up, and the current stops flowing in the circuit, but the appliance remains connected to the high potential point of the supply through the live wire. Now if someone touches the device, he/she can get a shock as the person will come in contact with the live wire through the appliance.
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