Practical Electricity - 15

When an electric current flows through a heating element, electrical energy is converted to heat energy due to high resistance in the heating element

(W) Watts and (J) Joules

$P = V\times I, \space I^2 \times R, \space \frac{V^2}{R}$

$(V \times I) \div 1000 \times t \space with \space t \space in \space hours$

$kWh \times (3.6 \times 10^6)$

$kWh \times cost$

So that switching them off / when the fuse blows / after a trip results in the disconnection of high voltage from an appliance, preventing it from running

It is a safety device which protects the equipment and wiring from excessive current. When a fuse experiences a current greater than its rated value, a short thin piece of wire becomes hot and melts, opening the circuit and cutting the current

It is a safety device that can switch off the electrical supply in a circuit when there is large current flowing through it. When there is a current surge, it will trip and cut off the current to the appliances

blue, brown & green and yellow

0, 240V, usually 0

It is a low resistance wire connected to the metal casing of the appliance, done to prevent users from getting electric shocks when there are faults

A safety feature which substitutes the earth wire where both the electrical cable is insulated from the terminal components of the appliance and internal metal parts are insulated from the non-metallic external casing

It is connected to a high voltage and carries the current from the wall plug to the appliance

It is there to close the circuit by providing a return path to the supply for the current, usually at 0V

It is a low resistance wire for carrying electrical current to the earth usually connected to the metal casing of appliances