Kettle how does it work

Before the advent of electric kettles, people used steam kettles. One had to place the kettles on the gas stove and the water boiled. The building pressure of the steam would push the lid, emitting a whistling sound alerting the user that the water was boiled. All this changed when in electric kettle was invented. This was further improved upon by adding a cool-touch handle and lid, preventing people from burning their hands.

When an electric kettle is plugged into an electric outlet and switched on — the electricity flows through the concealed heating element which contains metal coil. Electricity passes through the coil, turning into heat and warming water inside it. As an electric kettle is a sealed unit, the temperature rises quickly and pretty soon the water starts to boil. It was seen as an electrical hazard. A brief history When gas cook-tops became more widely available around years ago, the whistling kettle, otherwise known as a steam kettle became a popular kitchen appliance.

By , steam kettles were replaced with electric kettles, invented by Arthur Leslie. The coil has an electrical resistance a measure of the difficulty to pass an electric current through it. This resistance turns electrical energy into heat as it passes through coil. The heat brings the water inside it to boiling point. Some kettles use a thermostat, which prompts them to switch off when the water reaches the right temperature. The heating element is controlled by the thermostat.

The thermostat has a variable resistor inside. The higher you set the temperature, the lower the resistance is. A small current runs through the thermostat, usually controlling an electronic switch called a transistor.

The transistor, in turn, controls the heating element. When the resistance goes up in the thermostat, less current flows through, which causes less current to flow through the heating element. This keeps the heating element and the water cooler.

When the resistance is reduced, the current through the thermostat increases, which causes the transistor to increase the current through the heating element.