2006-08-06 07:02:43 · 6 answers · asked by ghost 1 in Science & Mathematics ➔ Physics
Whether a substance is transparent or not depends on two major factors - the wavelength of the light and the physical properties of the material in question.
Nearly every substance is transparent to some wavelengths of light and opaque to others.
Visible light has very little penetrating power if the atoms or molecules of the substance are not aligned just right.
To high energy light, such as x-rays and gamma rays, even stone and metals can be transparent.
Even whole planets can be transparent to some particles (such as neutrinos) which can pass through the entire Earth without even touching an atom in the process.
2006-08-06 16:41:26 · answer #1 · answered by Jay T 3 · 0⤊ 1⤋
Opaque objects do not let light through becaue they absorb all the energy the light has. The energy absorbed is then re-emitted as more light. For opaque objects, this re-emmision lead to either the light going out the same way it came in, or more light is absorbed by other atoms. The end effect is, the light is mostly thrown back out. with very little or nothing goes through.
2006-08-06 07:14:53 · answer #2 · answered by dennis_d_wurm 4 · 0⤊ 0⤋
Light intensity decays as exp(-mu_sub_a*x)*exp(-mu_sub_s*x) where mu_sub_a is the absorption coefficient and mu_sub_s is the scattering coefficient. The absorption coefficient is derived from the imaginary part of the refractive index. The scattering coefficient is related to fluctuations in the real part of the refractive index and serves to increase the effective path length through an absorbing material. The difference between opaque and transparent materials is just the magnitude of mu_sub_a. For a metal (opaque) the light decays to 1/e on a lenght scale of 1e-8 m, whereas a light in transparent material like water falls to 1/e in 1e2 m (visible). Note that the absorption coeficient is a function of wavelength. In the infrared light falls to 1/e in approximately 1e-5 m.
Optical Physicist
2006-08-06 07:46:59 · answer #3 · answered by d/dx+d/dy+d/dz 6 · 0⤊ 0⤋
There are different types of opaque solids. Metals don't let light through because it reflects any light falling on it.
Other materials are opaque because the consist of many small crystals. he boundarys between these crystals scatter light so none makes it through.
Other materials are opaque because the absorb the light in the manner described above.
2006-08-06 08:51:37 · answer #4 · answered by Itchyknee 2 · 0⤊ 0⤋
Light travels through opaque objects. However the light is absorbed very strongly, maybe 95%/cm.
The light energy transfers into thermal energy. That is heat.
Th
2006-08-06 07:44:59 · answer #5 · answered by Thermo 6 · 0⤊ 0⤋
Opaque objects have little tiny baseball batters that whack the light back.
2006-08-06 07:17:59 · answer #6 · answered by stevewbcanada 6 · 0⤊ 0⤋