Heat is a form of energy which exists naturally.
It quickly changes into different forms of energy like light, electricity, etc.
Life on this earth depends on heat energy for survival.
The man knew about heat and its precursor fire since ages and had been using it for various applications.
Heat energy, unlike other forms, can be felt by the sense of touch.
Importance of heat
Heat and energy are quite related and is known to man before advancements in science. It has a significant role in human lives and also the environment. Heat energy helps to
This heat energy trapped as carbohydrates again releases the heat in the body. The heat energy formed by break down of carbohydrates in the animal tissues. This heat is measured as body temperature and is kept uniform throughout the body by blood distribution.
Besides carbohydrates, heat energy is also stored in the form of fats and to some extent in proteins.
Thus energy in the form of heat is involved in food production and temperature maintenance of warm-blooded animals.
2. Enzyme reactions: Enzymes are bio-catalysts which help to enhance the speed of biochemical reactions. These enzymes operate only when there is a suitable temperature, i.e., heat energy. At low temperature, they are inactive, and the reactions do not proceed. At high temperature they get denatured (destroyed). Hence, they need optimal temperature for function. So without heat, they are non-functional. Therefore, you can notice that in case high body temperature like in disorder like sunstroke body become weak due to physiological dysfunction.
3. Water cycle: Water cycle is a phenomenon responsible for the rain and life on earth. When the heat from the sun contacts water on the earth, it evaporates by forming water vapor. This evaporation which mostly happens from the oceans to form the clouds. These vaporous clouds, in turn, reach the land through the sky, get cooled and cause rains. The rainwater collects in pools, ponds, rivers, etc. and the excess returns to seas and ocean. This cycle is called a water cycle and this happens due to heat gain and heat loss (cooling) mechanism. When the water gets heated, it evaporates from the earth and when the clouds get cooled, it causes rain on the planet. So heat from the sun is responsible for showers and life on earth.
During heat temperature in summers, even water on land also evaporates. The water vapor when rises above convert into clouds and cause rains when cooled. But most of the water is from oceans than from land.
4. Chemical reactions: Many chemical reactions like synthesis, breakdown occur in the presence of heat energy. Due to heat energy, the electrons and atoms in the substances which are in the stable state are set into vibration. These vibrations make it easy to form new bonds and new molecules. Thus heat brings in a change in molecules and substances. Hence you can even notice medicines containing label “store in a cool place.” This is because exposing them heat can lead to reactions and spoil the drug ingredient within.
5. Automobile motion: All the vehicles which run on petrol and coal operate due to the generation of heat energy within. The heat energy helps the pistons to move which is conveyed into cyclic motion and thus the wheels rotate. The more the heat generated, the more the speed and strength of the movement. Therefore heat energy is the base for all automotive vehicles like cars, buses, trucks, etc.
6. Cooking: Cooking is a daily routine at home followed by the man to make his food. Cooking helps keep the food tasty, easy to digest and also kill any microorganisms which might be harmful to health. Heat transference during cooking renders the food material and fiber more soft and pulpy.
7. Electricity generation from solar and earth: Electricity is generated by any means like by use of dam water, coal, nuclear energy, wind and even solar energy.
Of them, solar and coal methods employ the use of heat to generate electricity.
Especially coal is used in large quantities in many countries to generate heat and thereby electric current.
Even few advanced countries use geothermal energy (renewable) to generate electricity by safer means (non-polluting and harmful to the environment).
This geothermal energy also is heat inside the earth.
8. Melting and molding of metals: Metals are hardest substances which are used widely for building, vehicles, hardware, etc.
These metals cannot be molded with the application of pressure. But hey can be molded easily if heated.
9. Drying: Drying is done by removal of water from surfaces. This is possible by wind currents and even vacuum. But the most common method is by use of heat. Sun’s heat helps in drying clothes, soil and any other wet surfaces. Transferring heat to moist clothes set the water molecules into motion thereby they easily move away into the air leaving the cloth dry.
10. Sterilization: This is a process to kill any microbes in drugs and other healthcare material. This aims to keep the preparation sterile until use. So heat sterilization is the most common and highly effective methods of doing it. Methods like autoclave, hot air-oven, incineration use heat energy in the process of sterilization. But the process can be achieved at when the material is exposed to specific temperature and suitable duration of time.
11. Incubation to grow birds in the eggs: You might have heard that hens sit on their eggs to hatch them. After the hen lays its eggs, it sits on them and provides heat for the embryo in the egg to grow. It does so for 21 days after which a fully formed chick comes out of the egg. In general birds, the body is quite warm due to feathers and when they sit on their eggs, they pass on the heat. This heat energy helps in the growth of the embryo into a bird.