Table of Contents
- 1 How does surface affect radiation?
- 2 What effect does convection heat transfer from or to a surface have on the solid bounded by the surface?
- 3 How different surfaces affect the rate of thermal radiation absorption and emission?
- 4 Why does matte black absorb heat?
- 5 Why do you think dark surfaces absorb radiation better than light surfaces?
- 6 How would adding a reflective surface affect the temperature?
How does surface affect radiation?
The rate of heat transfer by emitted radiation is determined by the Stefan-Boltzmann law of radiation: Furthermore, the radiated heat is proportional to the surface area of the object. If you knock apart the coals of a fire, there is a noticeable increase in radiation due to an increase in radiating surface area.
What effect does convection heat transfer from or to a surface have on the solid bounded by the surface?
What effect does convection heat transfer from or to a surface have on the solid bounded by the surface? Convection is equal to the conduction in the surface.
What type of surfaces are good at reflecting radiation?
The amount absorbed, reflected and transmitted depends on the type of material. Dull, black, matte surfaces are good at absorbing radiation but not so good at reflecting it. White, shiny, smooth surfaces on the other hand are very good at reflecting radiation while these are poor at absorbing it.
Is radiation a surface phenomenon explain?
Thermal radiation emission is a direct result of vibrational and rotational motions of molecules, atoms, and electrons of a substance. However, for opaque solids such as metals, radiation is considered to be a surface phenomenon, since the radiation emitted by the interior region never reach the surface.
How different surfaces affect the rate of thermal radiation absorption and emission?
So the rule is – when an object that is hotter (higher temperature) than its surroundings, it will emit more radiation than it absorbs, and, an object that is cooler than its surroundings will absorb more radiation than it emits.
Why does matte black absorb heat?
Dark colors absorb a lot more heat than lighter ones because they absorb more light energy. In fact, the closer to black a color is, the more heat it absorbs from light sources.
Which heat transfer is characterized by heat traveling through fluids?
Convection is the movement of heat by a fluid such as water or air. The fluid (liquid or gas) moves from one location to another, transferring heat along with it. This movement of a mass of heated water or air is called a current. Radiation is the transfer of heat by electromagnetic waves.
What phase of matter holds convection as a significant mechanism for heat transfer quizlet?
What phase of matter holds convection as a significant mechanism for heat transfer? fluids.
Why do you think dark surfaces absorb radiation better than light surfaces?
Dark-colored materials absorb visible light better than light-colored materials. The lighter side absorbs less of the incident light, reflecting some of the energy. Darker materials also emit radiation more readily than light-colored materials, so they cool faster.
How would adding a reflective surface affect the temperature?
Reflective surfaces can deliver high solar reflectance (the ability to reflect the visible, infrared and ultraviolet wavelengths of the sun, reducing heat transfer to the surface) and high thermal emittance (the ability to radiate absorbed, or non-reflected, solar energy).
What is an opaque surface in radiation?
When solar radiation hits a surface, the photons can be absorbed, reflected, or transmitted. In the case of opaque (not transparent) materials, none of the photons are transmitted. If the material is dark and dull (not reflective or shiny), very few of the photons are reflected.
Which characteristics would absorb radiation the best?
Objects that are good emitters are also good absorbers (Kirchhoff’s radiation law). A blackened surface is an excellent emitter as well as an excellent absorber. If the same surface is silvered, it becomes a poor emitter and a poor absorber. A blackbody is one that absorbs all the radiant energy that falls on it.