Go Back   Physics Help Forum > High School and Pre-University Physics Help > Kinematics and Dynamics

Kinematics and Dynamics Kinematics and Dynamics Physics Help Forum

Reply
 
LinkBack Thread Tools Display Modes
Old Feb 14th 2016, 06:05 PM   #1
Member
 
timemachine2's Avatar
 
Join Date: Jan 2016
Posts: 45
Talking Think about this deeply, could any object become invisible/translucent if the eV of e

of silicon, sodium, and calcium do not excite electrons to higher shell levels, and there is no absorption, and emission in glass.
Then in SOLID Carbon, and hydrogen, and helium, which are elements in the human body.
If X-rays excited electrons in these elements to higher shell levels, shell 1, 2, and 3.
There must be higher shell levels/energy levels that do not excite red light.
If X-rays, and red light mixed together, or the red light was sent to electrons in millisecond bursts after the X-rays hit , I believe electrons would transmission the electrons, and you could make a object invisible.
Red light has the least amount of energy.
It has to work because there are more protons, neutrons, and electrons in silicon, sodium, and calcium, than carbon, hydrogen, and helium.
IT HAS TO WORK.
Think deeply about it fo a mind experiment on it.
Thank, you for your help, anything helps, even a few words.

Last edited by timemachine2; Feb 14th 2016 at 06:30 PM. Reason: more info
timemachine2 is offline   Reply With Quote
Old Feb 16th 2016, 10:54 AM   #2
Physics Team
 
ChipB's Avatar
 
Join Date: Jun 2010
Location: Morristown, NJ USA
Posts: 2,352
Originally Posted by timemachine2
IT HAS TO WORK
Apparently not. What you are suggesting is that when a person undergoes an X-ray at the doctor's office he should become transparent to visible light. Yet last time I had an X-ray taken by my dentist I did not become invisible.

I think the main reason why it doesn't work is two-fold:

1. Molecules are much more complex in terms of energy states available for electrons than individual atoms. So while most of the body's mass is made up of hydrogen, carbon and oxygen, the actual molecules such as water, hemoglobin, DNA, etc have many more possible energy states than would the constituent atoms on their own. Thus complex molecules in general are more likely to absorb photons and are hence less transparent than simple atoms.

2. It turns out that the higher electron energy levels of an atom or molecule are spaced closer together than is the spacing from from ground state to the first energy level. So the act of exciting the atoms and molecules with X-rays would in fact cause the material to become more likely to be able to absorb photons of varying energy levels, not less likely. The result would be that a material being exposed to x-rays would generally be even more opaque than if not exposed to x-rays.

Last edited by ChipB; Feb 16th 2016 at 12:58 PM.
ChipB is offline   Reply With Quote
Old Feb 16th 2016, 03:29 PM   #3
Member
 
timemachine2's Avatar
 
Join Date: Jan 2016
Posts: 45
Talking Dear chip B, thank you so much for your answers, not many reply to my questions.

In my mind I think because glass is made from silicon, sodium, and calcium, and these elements have more protons, neutrons, and electrons, than SOLID carbon, hydrogen, and helium.
Then if light does not excite the electrons in glass which is made from silicon, sodium, and calcium, then by exciting electrons in carbon to a higher energy shells , like 1, 2, 3, , or more there may be a shell level where the electron is in, that does not absorb certain wavelengths of light in eV.
Let's say the electron wants to jump from the first energy level, n = 1, to the second energy level n = 2. The second energy level has higher energy than the first, so to move from n = 1 to n = 2, the electron needs to gain energy.
It needs to gain (-3.4) - (-13.6) = 10.2 eV of energy to make it up to the second energy level.
So if you hit electrons in solid carbon with certain frequencies of light, while the electron is in certain shell levels briefly, there could be transmission, of the electron, not absorption.
To fully test this theory, I need to know the energy levels of the electrons in eV, of SOLID silicon, sodium, and calcium.
Then find the eV of electrons in shells 1, 2, and 3, in solid carbon.
Than I can get a idea of what eV in electrons in SOLID carbon does not excite certain wavelengths of light, especially red light which has the weakest energy.





Originally Posted by ChipB View Post
Apparently not. What you are suggesting is that when a person undergoes an X-ray at the doctor's office he should become transparent to visible light. Yet last time I had an X-ray taken by my dentist I did not become invisible.

I think the main reason why it doesn't work is two-fold:

1. Molecules are much more complex in terms of energy states available for electrons than individual atoms. So while most of the body's mass is made up of hydrogen, carbon and oxygen, the actual molecules such as water, hemoglobin, DNA, etc have many more possible energy states than would the constituent atoms on their own. Thus complex molecules in general are more likely to absorb photons and are hence less transparent than simple atoms.

2. It turns out that the higher electron energy levels of an atom or molecule are spaced closer together than is the spacing from from ground state to the first energy level. So the act of exciting the atoms and molecules with X-rays would in fact cause the material to become more likely to be able to absorb photons of varying energy levels, not less likely. The result would be that a material being exposed to x-rays would generally be even more opaque than if not exposed to x-rays.
timemachine2 is offline   Reply With Quote
Old Feb 17th 2016, 09:54 AM   #4
Physics Team
 
ChipB's Avatar
 
Join Date: Jun 2010
Location: Morristown, NJ USA
Posts: 2,352
One point of confusion is that it is not true that visible light does not excite electrons in glass. Stated another way - the electrons in glass absorb photons of visible light, but then re-radiate photons in a way that maintains the original photons energy and momentum. That's the secret of transparency of glass to visible light. We know that the atoms in glass absorb photons because the speed of light in glass is less than the speed of light in a vacuum - the process of absorption and re-emission of photons from atom to atom takes some time, hence the time it takes for a light signal to transition through a pane of glass is greater than if the glass atoms did not absorb the photons. The rate of this process depends on the energy levels being transitioned - this is what accounts for refraction of light and explains how a prism can separate white light into colors. If the photons were able to transition through glass without interacting with electrons then the glass would be transparent but would not be able to act as a prism or lens.
ChipB is offline   Reply With Quote
Old Feb 19th 2016, 12:33 PM   #5
Member
 
timemachine2's Avatar
 
Join Date: Jan 2016
Posts: 45
Talking Dear Chip

So light in glass is going in a straight line to illuminate the object making it transparent, in glass, but in another solid object the emission of the photon is going in another direction, not the original photons directions, with its energy, and momentum, which does not make the object, that is not glass transparent.
Is this correct.
There has to be no reason for the electrons energy levels to not be excitable to red light, or other EM, in solid objects like solid carbon.
Glass is made from silicon, sodium, and calcium, which has more protons, neutrons, and electrons than solid carbon.
Don't you just have to find the right eV levels in electrons shell levels in solid carbon, to not excite the electron with certain wavelengths of light.

Originally Posted by ChipB View Post
One point of confusion is that it is not true that visible light does not excite electrons in glass. Stated another way - the electrons in glass absorb photons of visible light, but then re-radiate photons in a way that maintains the original photons energy and momentum. That's the secret of transparency of glass to visible light. We know that the atoms in glass absorb photons because the speed of light in glass is less than the speed of light in a vacuum - the process of absorption and re-emission of photons from atom to atom takes some time, hence the time it takes for a light signal to transition through a pane of glass is greater than if the glass atoms did not absorb the photons. The rate of this process depends on the energy levels being transitioned - this is what accounts for refraction of light and explains how a prism can separate white light into colors. If the photons were able to transition through glass without interacting with electrons then the glass would be transparent but would not be able to act as a prism or lens.

Last edited by timemachine2; Feb 19th 2016 at 12:39 PM. Reason: new stuff
timemachine2 is offline   Reply With Quote
Reply

  Physics Help Forum > High School and Pre-University Physics Help > Kinematics and Dynamics

Tags
deeply, invisible or translucent, object



Thread Tools
Display Modes


Similar Physics Forum Discussions
Thread Thread Starter Forum Replies Last Post
Can any INVISIBLE EM waves get electrons in solid matter, to noabsortion1 Advanced Optics 2 Apr 23rd 2016 10:12 AM
Is it possible to combine invisible EM waves together to pass through a object, while noabsortion1 Light and Optics 0 Apr 21st 2016 02:01 PM
Would any solid element be invisible/transparent if you could stop electrons from abs invisibletransparent Light and Optics 1 Mar 22nd 2016 05:27 PM
Weight of object = Force of buoyancy: can I use this when density of object is greatr jlyu002 Thermodynamics and Fluid Mechanics 2 Aug 13th 2014 06:44 AM
How to become invisible werehk Light and Optics 5 Apr 28th 2014 11:54 PM


Facebook Twitter Google+ RSS Feed