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likephysics
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Why does a hot object emit Infra red light. How are photons are emitted from it?
likephysics said:Why does a hot object emit Infra red light. How are photons are emitted from it?
physixlover said:light is emitted when the atom jumps from excited state to ground state,when the object is heated,heat energy is supplied to the object,which causes rearrangement of the electrons,this occurs when the atoms are in excited state ,they come back to the lower energy level
conway said:This is probably not the correct mechanism for infrared emission.
For one thing, this explanation seems to require that the object is immersed in an existing bath of radiation; in fact, a black body emits just as much energy if it is located in the deepest depths of interstellar space, surrounded by the cold of absolute zero.
conway said:In a solid at rest, there is positive charges cancel the negative charges. In a mechanically vibrating solid, it seems unlikely that the total positive charge centers (the nucleii) and the total negative charge (the electrons in orbitals and whatever free electrons are present in a metal) would necessarily be vibrating exactly in sync. If there is any net lag between the vibration of the positive and negative charges, then there would be a net vibrating charge which ought to radiate.
likephysics said:Net vibrating charge which ought to radiate.
At what frequency should the charges vibrate so they radiate IR? Should it be in terahertz? Can heat make the charges vibrate at such high frequency.
Claude Bile said:Conway is on the mark;
Objects whose temperature is above 0 K possesses thermal energy. Thermal energy, on a molecular level is simply the kinetic + potential energy of the particles. That is, in hot objects, the atoms that make up the object tend to wiggle around.
Now, in the process of wiggling around, negative charges displace from positive charge forming dipoles. Oscillating dipoles emit EM waves, which is why objects emit black-body radiation.
Claude.
conway said:For purposes of discussion, this is the kind of thing that most people probably just assume as a convenient starting point. The actual mechanism isn't that easy to explain but it's basically the same principle that makes a radio transmitter work.
conway said:Sorry, but I'm not sure anyone is going to be able to explain this. I'm not about to try.
physixlover said:i understood what you said, can you please clarify me how 'Oscillating dipoles emit EM waves'
Claude Bile said:Now, in the process of wiggling around, negative charges displace from positive charge forming dipoles. Oscillating dipoles emit EM waves, which is why objects emit black-body radiation.
physixlover said:i understood what you said, can you please clarify me how 'Oscillating dipoles emit EM waves'
Infrared emission is a form of electromagnetic radiation that is emitted by objects with high temperatures. It has a longer wavelength than visible light and is invisible to the human eye.
The amount of IR emission from an object is directly proportional to its temperature. As the temperature of an object increases, the amount of IR emission it produces also increases.
Yes, all objects with a temperature above absolute zero (-273.15 degrees Celsius) emit some amount of IR radiation. However, the amount of IR emission may be too low to be detectable by our eyes or IR sensors.
IR emission plays a crucial role in studying the thermal properties of objects and understanding their temperature. It is also used in various fields such as astronomy, medicine, and environmental science for remote sensing and thermography.
IR emission has a longer wavelength than visible light, making it invisible to the human eye. It is also less energetic than visible light and is primarily emitted by objects with higher temperatures, while visible light can be emitted by objects at room temperature.