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Physicsissuef
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Why we can see light and we can not see heat? Why can't heat be reflected?
By heat I assume you mean thermal radiation. If this is the case then the reason is that the photo receptors in our eyes are only sensitive to wavelengths between roughly 400nm to 700nm and thermal radiation has a wavelength greater than 700nm.Physicsissuef said:Why we can see light and we can not see heat?
What makes you think it can't?Physicsissuef said:Why can't heat be reflected?
Physicsissuef said:Why we can see light and we can not see heat? Why can't heat be reflected?
UV Heat?YellowTaxi said:Some animals can see heat (either infrared or ultra-violet).
This caused a bit of a hullaballo a few years back when people realized their HandyCams were recording the naughty bits of their loved ones right through their clothes. Manufacturers hastily installed filters in their cams to prevent this. But the filters can be removed...YellowTaxi said:Just like some electronic cameras easily detect infra-red, at no extra cost.
Just to make one thing clear, heat is not temperature nor is it energy. Heat is the transfer of energy from a higher temperature to lower temperature, something cannot have "heat", and to say that something "has heat" is non-nonsensical. One can think of heat as the microscopic analogy of work.RonL said:Heat is a measure of energy content, that can be felt, or observed...
Physicsissuef said:Why can't heat be reflected?
Hootenanny said:Just to make one thing clear, heat is not temperature nor is it energy. Heat is the transfer of energy from a higher temperature to lower temperature, something cannot have "heat", and to say that something "has heat" is non-nonsensical. One can think of heat as the microscopic analogy of work.
First, the flame increases the internal energy of the steal, by transferring energy to the steel, this energy transfer is called heat as opposed to work which would be done if the steel bar were compressed. When the flame is removed, the steel bar begins to radiate energy to it's surroundings and it's temperature decreases. This thermal radiation is known as heat.RonL said:I'm confused If at 1200 degrees, i remove the flame used to bring the temperature up, how do you describe the state of the steel until it cools to room temperature ?
Light and heat are both forms of energy, but they differ in the way they interact with matter. Light is a type of electromagnetic radiation that can be detected by our eyes, while heat is the transfer of thermal energy between objects. Our eyes have specialized cells called rods and cones that are sensitive to light, allowing us to see it. However, we do not have cells that can detect heat in the same way.
Light can interact with matter in several ways, including reflection, absorption, and transmission. When light hits an object, it can either bounce off (reflection), be absorbed by the object, or pass through it (transmission). The color of an object is determined by which wavelengths of light it reflects or absorbs.
All objects with a temperature above absolute zero give off heat in the form of thermal radiation. However, not all objects emit light. The amount of light an object emits depends on its temperature and the type of material it is made of. For example, a piece of metal may feel hot to the touch but not emit light, while a flame is both hot and produces light.
No, light and heat are not always present together. For example, a laser beam can be hot enough to burn through metal, but it does not give off heat in the traditional sense. This is because the energy of the laser is focused in a small, concentrated area, rather than being dispersed as heat.
The speed of light is much faster than the speed of heat. Light travels at approximately 299,792,458 meters per second, while heat travels at a much slower pace. In fact, the speed of heat can vary depending on the material it is traveling through, while the speed of light is constant in a vacuum.