when light falls on a object it can be absorbed reflected or allowed to pass through. what does an opaque do? how do we see it
Answers
Explanation:
Light is an electromagnetic wave. An electric field and magnetic field oscillate back and forth. For most light the directions of the waves are oriented in all different direction - The light is not polarized.
Electrons have a charge, so when the magnetic wave of light reaches them it pushes them around, just like any magnetic field will affect something with charge. But being very light, electrons, depending on the material they are part of, can respond and move very quickly back and forth in response to the light. What happens when a charged particle moves back and forth very quickly? It emits its own electromagnetic wave! Those new waves interact with the original wave, and depending on the material, and how free the electrons are in that materials, those waves might cancel out the original wave (opaque), or the electrons might be held so tightly that they don’t cancel out at all (clear). And because those new waves emit their waves in all directions, including back toward the light source or off to the side, that new light goes off in all directions so we can see them, and thus see the object.
Visible light has a range of wavelengths, and different materials hold their electrons in such a way that they can move when wobbled at certain frequencies, but are held tight at other frequencies. If a material has electrons that wobble well under red light, then those electrons will re-emit red light - Out of phase into the material (the material will be opaque as the out-of-phase light cancels the original light), but the new red light will go all directions, including back toward us so we can see the object - The red object.
Some materials have the interesting property that their electrons, instead of simply wobbling back and forth to generate electromagnetic waves, will actually store the energy from the wave by having their electrons jump to a higher orbital in their atoms. They might do this by absorbing the energy from several interacting waves of different frequencies. Then, sometime later, as the electron falls back to a lower orbital, it will emit a new photon of light of a particular frequency corresponding to the difference in energy between those two orbitals, and that frequency might be completely different than the originally absorbed light waves. Phosphorous compounds often have this property, so it is calls phosphorescence. With some compounds, like those used to convert blue LEDs or UV fluorescent lights to visible light, the re-emitted light might happen within a fraction of a second, whereas in other compounds, like the ones in your glow-in-the-dark Frisbee, re-emit their green light absorbed from your bluish electronic flash over the course of 5 minutes.
Answer:
Light is an electromagnetic wave. An electric field and magnetic field oscillate back and forth. For most light the directions of the waves are oriented in all different direction - The light is not polarized.
Electrons have a charge, so when the magnetic wave of light reaches them it pushes them around, just like any magnetic field will affect something with charge. But being very light, electrons, depending on the material they are part of, can respond and move very quickly back and forth in response to the light. What happens when a charged particle moves back and forth very quickly? It emits its own electromagnetic wave! Those new waves interact with the original wave, and depending on the material, and how free the electrons are in that materials, those waves might cancel out the original wave (opaque), or the electrons might be held so tightly that they don’t cancel out at all (clear). And because those new waves emit their waves in all directions, including back toward the light source or off to the side, that new light goes off in all directions so we can see them, and thus see the object.
Explanation: