Table of Contents
- 1 Why is radiation considered a surface phenomenon?
- 2 Why thermal radiation in solids is treated as a surface phenomenon?
- 3 What is phenomenon when radiation absorbed by the atmosphere?
- 4 What are the radiation surface and space resistances how are they expressed for what kind of surfaces is the radiation surface resistance zero?
- 5 What type of radiation is emitted from the Earth’s surface?
- 6 How does radiation heat of the atmosphere?
Why is radiation considered a surface phenomenon?
Radiation is a volumetric phenomenon, though for opaque surfaces (e.g. Metals, wood, and rocks) it is considered to be a surface phenomenon as the radiation emitted by the interior regions of the material can never reach the surface.
Why thermal radiation in solids is treated as a surface phenomenon?
Thermal radiation can be viewed as a surface phenomenon because thin surface layers (− 0.001 to 1 mm) on the body are involved in the radiative heat transfer. Bodies can radiate energy of all wavelengths λ = 0 – ∞ (a continuous spectrum) or selectively to a specific wavelength range (selective spectrum).
Why are metals opaque to electromagnetic radiation having photon energies within the visible spectrum?
21.4 Briefly explain why metals are opaque to electromagnetic radiation having photon energies within the visible region of the spectrum. The light energy is totally absorbed or reflected, and, since none is transmitted, the material is opaque.
How electromagnetic radiation affects matter when it is absorbed by matter?
The different parts of the electromagnetic spectrum have very different effects upon interaction with matter. If electromagnetic energy is absorbed, but cannot eject electrons from the atoms of the material, then it is classified as non-ionizing radiation, and will typically just heat the material.
What is phenomenon when radiation absorbed by the atmosphere?
When referring to the Earth’s climate, greenhouse effect is the heating of the planet’s surface due to the absorption of outgoing infrared or thermal radiation due to atmospheric greenhouse gases such as methane, carbon dioxide, and water vapour. …
What are the radiation surface and space resistances how are they expressed for what kind of surfaces is the radiation surface resistance zero?
For what kind of surfaces is the radiation surface resistance zero? Radiation surface resistance represents the resistance of a surface to the emission of radiation. It is zero for surfaces with emissivity of 1. The space resistance is the radiation resistance between two surfaces.
How does radiation absorb matter?
In physics, absorption of electromagnetic radiation is how matter (typically electrons bound in atoms) takes up a photon’s energy — and so transforms electromagnetic energy into internal energy of the absorber (for example, thermal energy).
Why does radiation interact with matter?
The main effect radiation has on matter is its ability to ionize atoms to become ions, a phenomenon known as ionization, which is very similar to the photoelectric effect. Radioactive particles or electromagnetic waves with sufficient energy collide with electrons on the atom to knock electrons off the atom.
What type of radiation is emitted from the Earth’s surface?
infrared
Radiation emitted from Earth is called longwave radiation; it falls within the infrared portion of the spectrum and has typical wavelengths of 4 to 30 micrometres (0.0002 to 0.001 inch). Wavelengths of radiation emitted by a body depend on the temperature of the body, as specified by Planck’s radiation law.
How does radiation heat of the atmosphere?
Convection is the transfer of heat energy in a fluid. Air in the atmosphere acts as a fluid. The sun’s radiation strikes the ground, thus warming the rocks. As the rock’s temperature rises due to conduction, heat energy is released into the atmosphere, forming a bubble of air which is warmer than the surrounding air.