Examples of heat transfer in nature, at home

Thermal energy is a term that we use to describe the level of activity of molecules in an object. Increased excitement, one way or another, is associated with an increase in temperature, while in cold objects, atoms move much more slowly.

Examples of heat transfer can be found everywhere - in nature, technology and everyday life.

Examples of heat transfer

The largest example of heat transfer is the sun, which warms the planet Earth and everything that is on it. In everyday life, you can meet a lot of these options, only in a much less global sense. So, what examples of heat transfer can you observe in everyday life?

Here are some of them:

• A gas or electric stove and, for example, a frying pan for frying eggs.
• Automotive fuels, such as gasoline, are sources of thermal energy for the engine.
• The included toaster turns a piece of bread into a toast. This is due to the radiant heat energy of the toast, which draws moisture from the bread and makes it crunchy.
• A hot cup of steaming cacao warms your hands.
• Any flame, from a match flame to massive forest fires.
• When the ice is placed in a glass of water, the heat energy from its water melts, that is, water itself is the source of energy.
• The radiator or heating system in the house provides heat during the long and cold winter months.
• Conventional furnaces are sources of convection, as a result of which the food product placed in them is heated, and the cooking process is started.
• Examples of heat transfer can also be observed in your own body, taking a piece of ice in your hand.
• Thermal energy is even inside the cat, which can warm the knees of the host.

Heat is movement

Heat flows are in constant motion. The main methods of their transfer can be called a convention, radiation and conductivity. Let's look at these concepts in more detail.

What is conductivity?

Perhaps, many people have noticed more than once that in the same room, the sensations of touching the floor can be completely different. It is nice and warm to walk on the carpet, but if you go to the bathroom with bare feet, a tangible cool immediately gives a feeling of vivacity. Only not in the case where there is heated floors.

So why is the tiled surface freezing? It's all because of the thermal conductivity. This is one of three types of heat transfer. Whenever two objects of different temperatures are in contact with each other, thermal energy will pass between them. Examples of heat transfer in this case can be summarized as follows: by holding onto a metal plate, the other end of which is placed above the candle flame, you can feel burning and pain in time, and when you touch the iron handle of a pot of boiling water, you can get a burn.

Conductivity factors

Good or poor conductivity depends on several factors:

• The type and quality of the material from which the objects are made.
• The surface area of two objects in contact.
• The temperature difference between the two objects.
• Thickness and size of objects.

In the form of an equation, it looks like this: the rate of heat transfer to the object is equal to the thermal conductivity of the material from which the object is made multiplied by the surface area in the contact multiplied by the temperature difference between the two objects and divided by the thickness of the material. It's simple.

Conductivity examples

Direct heat transfer from one object to another is called conductivity, and substances that conduct heat well are called conductors. Some materials and substances do poorly this task, they are called insulators. These include wood, plastic, fiberglass and even air. As is known, insulators do not actually stop the flow of heat, but simply slow it down to some extent.

Convection

This kind of heat transfer, like convection, occurs in all liquids and gases. You can find such examples of heat transfer in nature and in everyday life. When the liquid is heated, the molecules in the lower part gain energy and start moving faster, which leads to a decrease in density. The warm fluid molecules begin to move upward, while the cooler (the denser liquid) begins to sink. After the cool molecules reach the bottom, they again get their share of energy and again aspire to the top. The cycle continues as long as there is a heat source at the bottom.

Examples of heat transfer in nature can be summarized as follows: using a specially equipped burner, warm air, filling the balloon space, can lift the entire structure to a sufficiently high altitude, the whole point is that warm air is lighter than cold air.

Radiation

When you sit in front of a fire, you warm the warmth that comes from him. The same happens if you put your hand to the burning light bulb, without touching it. You too will feel the heat. The largest examples of heat transfer in everyday life and nature are led by solar energy. Every day the heat of the sun passes through 146 million km of empty space right up to the Earth itself. This is the driving force for all forms and systems of life that exist on our planet today. Without this method of transmission, we would be in great trouble, and the world would not be the same as we know it.

Radiation is the transfer of heat through electromagnetic waves, whether it be radio waves, infrared, X-rays or even visible light. All objects radiate and absorb radiant energy, including the person himself, but not all objects and substances cope with this task equally well. Examples of heat transfer in everyday life can be considered using a conventional antenna. As a rule, what radiates well is also good and absorbs. As for the Earth, it takes energy from the sun, and then gives it back into space. This radiation energy is called terrestrial radiation, and this is what makes life on the planet possible.

Examples of heat transfer in nature, life, technology

Transmission of energy, in particular heat, is a fundamental area of research for all engineers. Radiation makes the Earth suitable for habitation and gives renewable solar energy. Convection is the basis of mechanics, responsible for airflows in buildings and air exchange in homes. Conductivity allows you to heat the pan, just by putting it on the fire.

Numerous examples of heat transfer in engineering and nature are obvious and are found everywhere in our world. Almost all of them play a big role, especially in the field of mechanical engineering. For example, when designing a building ventilation system, engineers calculate the heat transfer of a building in its vicinity, as well as internal heat transfer. In addition, they select materials that minimize or maximize heat transfer through individual components to optimize efficiency.

Evaporation

When atoms or molecules of a liquid (for example, water) are exposed to a significant volume of gas, they tend to spontaneously enter a gaseous state or evaporate. This is because the molecules are constantly moving in different directions at random speeds and collide with each other. In the course of these processes, some of them receive kinetic energy sufficient to repel the source of heating.

However, not all molecules can evaporate and become water vapor. It all depends on the temperature. Thus, the water in the glass will evaporate more slowly than in the pan heated on the stove. The boiling of water greatly increases the energy of the molecules, which, in turn, accelerates the evaporation process.

Basic concepts

• Conductivity is the transfer of heat through matter with direct contact of atoms or molecules.
• Convection is the transfer of heat through the circulation of gas (for example, air) or liquid (for example, water).
• Radiation is the difference between the absorbed and reflected heat quantity. This ability is strongly dependent on color, black objects absorb more heat than light ones.
• Evaporation is a process in which atoms or molecules in a liquid state receive enough energy to become a gas or vapor.
• Greenhouse gases are gases that trap the heat of the sun in the Earth's atmosphere, producing a greenhouse effect. There are two main categories - water vapor and carbon dioxide.
• Renewable energy sources are unlimited resources that are replenished quickly and naturally. Here are the following examples of heat transfer in nature and technology: the winds and energy of the sun.
• Thermal conductivity is the rate at which the material transfers heat energy through itself.
• Thermal equilibrium is a state in which all parts of the system are in the same temperature regime.

Application in practice

Numerous examples of heat transfer in nature and technology (the pictures above) indicate that these processes should be well studied and served for good. Engineers apply their knowledge of the principles of heat transfer, explore new technologies that involve the use of renewable resources and are less damaging to the environment. The key point is the understanding that the transfer of energy opens up infinite possibilities for engineering solutions and not only.