Places near the stove feel warmer than places far away. This is due to the direct transfer of heat from the stove without the movement of matter. This direct transfer of heat without the aid of a substance is called radiation.When using an infrared curing machine or cooking in an oven, thermal energy is transmitted by radiation.
There is no medium between the sun and the earth, but heat is transferred to the earth. So you can see that heat is transferred by radiation.
Radiation Equilibrium of the Earth
The earth’s temperature is kept constant only when the earth emits the same amount of radiant energy from the sun. This is called the radiation equilibrium of the earth.
Greenhouse effect, Global warming.
All objects that have a temperature emit radiant energy in the form of light (electromagnetic waves). The higher the temperature, the shorter the wavelength of light, and the lower the temperature, the longer the wavelength.
The sun has a surface temperature of about 6000K and emits mainly visible light. Earth’s surface temperature is lower than the sun, as we know. The light emitted by the earth is mainly an infrared region.
Due to the different wavelengths of radiant energy that the Earth sends and receives, the radiation equilibrium temperature may vary. For example, when the carbon dioxide or methane gas increases in the atmosphere due to the industrial activities of humanity, more infrared rays are absorbed and released than before.
This greenhouse effect raises the global average temperature.
Global warming causes climate change, extreme droughts and floods, crop damage, pests, etc., and this can be a problem for humankind.