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The Basics of Electricity. Current and Voltage An electric current is the movement of electrons ( negative charges ). Current is measured in units called Amps ( A ). In a conductor ( all metals, carbon ) the electrons are free to move .
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The Basics of Electricity Current and Voltage An electriccurrent is the movement ofelectrons ( negative charges ). Current is measured in unitscalled Amps ( A ). In a conductor ( all metals, carbon ) the electronsare free to move. If the conductor is connected to a voltage supply ( mains, battery ) the electrons are given theenergythey need to move. Voltage is measured in units called Volts ( V ).
electrical kinetic electrical heat electrical light electrical sound Appliances The mainsand a battery supply electrical energy. Appliances change this electrical energy to another form. Some typical main energy changes that take place in everyday appliances: AplicaciónEnergy Change Kettle Lamp Radio Food Mixer
Power The Powerof an appliance tells us how quickly it uses up electrical energy. Power is measured inunits called Watts ( W ). High Power appliances need a bigger electric current.
Fuses Every appliance has a fuse ( usually found in its plug ). The fuse protects the flex connecting the appliance from overheating. If too large a current flows through the flex the fuse melts. The gap created means no current can flow and the appliance is safe. Appliances usually need a 3 A or a 13 A fuse. These are the maximum currents that can flow before the fuse melts.
What energy do appliances with the biggest Powers produce? What size of fuse do appliances with a Power greater than 700 W need? What about appliances with a Power less than 700 W? What appliances are exceptions to this rule? Why do these appliances require a bigger fuse? Heat Energy appliances have the biggest Powers Power more than or equal to 700 W needs a 13 A fuse Power less than 700 W needs a 3 A fuse Fridge and a hoover are exceptions They both have an electric motor
Choosing a Fuse Appliances with a power rating up to 700 W: use a 3A fuse Appliances with a power rating greater than 700 W: use a 13 A fuse
Flexes A flex connects an appliance to a plug. Appliances with a bigger power require a thicker flex.