The kettle is switched on. Determine the current in the heater.
The kettle manufacturer says that the kettle cable is safe for currents below 15 A. The wiring in the mains power supply in the wall is safe for currents below 20 A. The fuses available for the kettle are rated 3 A, 5 A, 7 A, 10 A, 13 A, 15 A, 18 A, 20 A, 25 A. State which fuse from these is the most suitable. Explain why it is the most suitable.
The cable that connects the kettle to the mains power supply contains three wires: the earth wire, the live (line) wire, the neutral wire. The wires are all connected properly. State the name of the wire in which the fuse is connected. Explain why the fuse is connected into this wire.
The insulation on the live wire is damaged, leaving the wire exposed. Explain what happens when the exposed live wire touches the metal outer casing.
The kettle is on for a total of 34 h over one year. The price of electricity is $0.32 per kilowatt-hour (kWh). Determine the cost of using the kettle during the year.