The Science Behind Why the Kettle on the Stove gets Hot

By Charlotte Dim

Updated on:

Households frequently have electric kettles, especially for people who want a quick cup of tea or coffee. Have you ever thought about how an electric kettle truly functions, though? Why the kettle on the stove gets hot?

The laws of heat transmission and thermodynamics are demonstrated by the simple act of setting a kettle on a burner and witnessing cold water turn into a steamy jet of vapour. 

In this article, I’ll discuss into the fascinating science behind why a kettle placed on a stove gets hot and brings water to a boil.

Materials Used in The Construction Of Heating Elements

The two materials used most frequently to make heating elements are stainless steel and nichrome, a nickel-chromium alloy. Because of its high electrical resistance, which effectively converts electrical energy into heat, nichrome is chosen. 

Contrarily, stainless steel is more robust and resistant to corrosion, making it the best material for immersion heating elements that come into contact with water.

The rate of water heating increases with increasing wattage. However, more power is used by higher wattage heating elements, which can raise your electricity costs.

Material used in why the kettle on the stove gets hot are mentioned below.

Circuitry for electricity:

Electricity, which is supplied to the kettle through an electrical circuitry system, powers electric kettles. 

A power supply, a control system, and several safety elements that guarantee the safe functioning of the kettle are some of the components that make up this system.

The power supply is in charge of converting the household’s AC (alternating current) voltage into the kettle’s necessary DC (direct current) voltage. 

Usually, a transformer and a rectifier circuit are used to do this. The bridge rectifier converts the lower AC voltage, which was reduced by the transformer, into DC voltage. The heating element is then given the DC voltage.

Electric kettles have a thermal fuse, a boil-dry protection feature, and an automated shut-off feature integrated into its circuitry. When the water boils or the kettle is removed 

Why the Kettle on the Stove gets Hot

Heating Element:

It is composed of a coil of wire that produces heat when an electrical current passes through it; the coil is often made of a high-resistance material.

In order to heat the water in the kettle, the heating element must first convert electrical energy into heat energy. 

The British physicist James Prescott Joule, who made this discovery in the middle of the 1800s, is credited with giving this process the name “Joule heating.”

Electric kettles typically employ one of two types of heating elements:

Immersion heating elements:

These are constructed of a metal tube that is submerged in water, and the heating element inside the tube heats the water as the current flows through it.

Surface heating elements: 

These are situated on the bottom or sides of the kettle and can be flat or helical in shape. Conduction is how the element’s heat is delivered to the water.

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Types Of Heating Elements Used in Electric Kettles

A thermostat, a temperature sensor, and a timer normally make up an electric kettle’s control system. By turning the heating element on and off as needed, the thermostat controls the water’s temperature. 

Thermal Energy Transfer: The Foundation

Thermal energy transmission is the primary force behind the heating of a kettle on a stove. The motion of particles within a substance, like the water molecules in the kettle, is what is known as thermal energy, a sort of kinetic energy. 

Due to their temperature, these molecules are constantly in motion, and as heat is added, this motion becomes more pronounced.

Conduction: A Direct Pathway

Conduction is the primary mechanism by which heat is transferred when a kettle is placed on a hot stove. Without any actual material movement, conduction is the direct transfer of heat from one object to another through physical touch.

The base of the kettle receives thermal energy as the stove’s hob warms up. The molecules at the site of contact gain energy, which causes them to move with more kinetic force. 

When these extremely energetic molecules hit with nearby molecules, energy is transferred as a result. This energy transmission spreads progressively to additional kettle components through the metal base of the kettle.

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Convection: Circulating the Heat

The method of heating the kettle mostly relies on conduction, although convection also plays a significant role. 

Convection is the movement of fluids (liquids or gases) to transfer heat. Conduction heat absorption causes the water molecules in the kettle’s bottom to become less dense, which causes them to rise to the surface.

As a result of this mechanism, warmer water rises and cooler water sinks, forming a convection current. 

All of the water is heated to the proper temperature because of the continual movement of the water, which helps the heat be distributed more evenly throughout the kettle.

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Boiling Point and Phase Change

The water within the kettle starts to get hotter as it continues to accept heat energy from the stove. The boiling point is the critical point at which the water molecules finally arrive. 

The temperature at which a liquid’s vapour pressure reaches equilibrium with air pressure, turning it into vapour or steam, is known as the boiling point. 

The water molecules on the water’s surface now possess sufficient energy to dislodge the forces holding them together in the liquid state. 

Many kettles create the distinctive whistling sound when they are about to pour when these gases escape into the atmosphere as steam.

You can securely and successfully use an electric kettle to boil water for your tea, coffee, or other hot beverages by adhering to these safety measures.

Can You Plugs That Get Hot?

The outside casing as well as the casing enclosing the inside wiring may burn and melt in an overheated electrical outlet, generating an unpleasant foul scent. However, if they get too hot, they may also cause electrical fires or even shock humans. In other words, it might be highly risky.

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Frequently Asked Questions about Why the Kettle on the Stove Gets Hot:

Question No.1: What is the primary mechanism through which heat is transferred from a stove to a kettle placed on it? 

Answer: The primary mechanism is conduction. Conduction is the direct transfer of heat from one object to another through physical contact.

Question No.2: How does convection contribute to the process of heating a kettle on a stove? 

Answer: Convection plays a role by creating a convection current within the kettle. As the water near the bottom gets heated and becomes less dense, it rises to the surface, allowing for more even heat distribution.

Question No.3: What is the boiling point of a liquid, and why is it important in the context of heating a kettle? 

Answer: The boiling point is the temperature at which the vapor pressure of a liquid matches the atmospheric pressure, causing the liquid to change into vapor or steam. It’s important because it indicates when the water in the kettle is ready to boil.

Question No.4: How does the movement of water molecules change as the kettle gets heated? 

Answer: As the kettle gets heated, the water molecules gain energy and their kinetic motion intensifies. This results in increased movement, with hotter water rising to the top and cooler water sinking to the bottom due to convection currents.

Question No.5: Why does the base of the kettle get hotter than the top when placed on a stove?

Answer: The base of the kettle gets hotter because heat is primarily transferred through conduction from the stove to the kettle’s base. The heat energy then spreads through the kettle, but the base receives the initial direct contact with the heat source.

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Why the kettle on the stove gets hot a symphony of thermal physics. The base of the kettle receives heat energy from the stove’s hob by conduction and convection, gradually boosting the water’s temperature. 

The well-known hissing sound that indicates the water is ready is made as the water transitions from liquid to steam at its boiling point.

Think about the complex dance of particles and energy that makes it all possible the next time you use your kettle to create a hot cup of tea or a bowl of muesli. 

The theory behind warming a kettle on the stove is a stunning example of how thermodynamics works in practise.

Charlotte is a seasoned writer and an established authority in the field of kitchen appliances. With a keen interest in culinary arts and a passion for providing practical guidance to consumers, Charlotte has dedicated years to researching and reviewing various kitchen products, including kettles.

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