Basic questions of electromagnetic radiation

[Helicobacter]

1. How do we observe what goes through in a slit in the double slit experiment? If this is accomplished with EM that goes across the slit, then why does the electron not completely change its direction before it hits the wall. It still always hit the wall where you expect it to, even though the photon collides with the electron that goes through the slit.
2. Can you reproduce this double split experiment with shooting through photons and neutrinos instead of electrons?
3. Say I use an extremely powerful optical microscope to zoom into matter. After what scale will I not see colors anymore? Will this be a continual process (i.e., the color fades more and more almost continuously) or does the colors simply vanish at some critical point?
4. Let's say there were a machine that could produce EM at different wavelengths and I dial it more and more into the shorter wavelangths from the visible light onwards (in a dark room). After a certain wavelength has passed (700nm), will it suddenly go dark or will I still see some violet until is slowly vanishes? (I assume the answer to this answer the question on the infrared side as well.)
5. Why do we use microwaves to heat food and not infrared?
6. Why do microwaves cause cancer and infrared does not? (should have asked this in the bio section probably).

 

[Helicobacter]

any nontrivial subset of answers is appreciated.

 

[Drakkith]

1. How do we observe what goes through in a slit in the double slit experiment? If this is accomplished with EM that goes across the slit, then why does the electron not completely change its direction before it hits the wall. It still always hit the wall where you expect it to, even though the photon collides with the electron that goes through the slit.

First, we cannot ever say with certainty where the electron will end up. We can only say that it has a certain chance of being detected in a certain location. When we observe the electron before it goes through the slit we don't see the wave-like properties of the electron and only see the particle-like properties.

2. Can you reproduce this double split experiment with shooting through photons and neutrinos instead of electrons?

Absolutely. You can perform the double slit experiment at home using a laser pointer. If you are interested just do a google search and you should find plenty of sites explaining how to set it up. Doing this with neutrino's isn't feasible as they interact with normal matter so little. But, if we could shoot enough neutrinos through so that we could see a pattern build up it would be the same as the electrons and photons produce. IE they would interfere and produce an interference pattern.

3. Say I use an extremely powerful optical microscope to zoom into matter. After what scale will I not see colors anymore? Will this be a continual process (i.e., the color fades more and more almost continuously) or does the colors simply vanish at some critical point?

Neither. When you zoom into with a microscope, you must illuminate your object with more light as you zoom in. Near the maximum limit most objects are mostly transparent, with the edges standing out since they absorb more light. Whatever color you are illuminating the object with is what you will see as the background light. If you didn't provide more illumination as you zoomed in, you would spread the available light out too much for anything to be visible to the naked eye.

4. Let's say there were a machine that could produce EM at different wavelengths and I dial it more and more into the shorter wavelangths from the visible light onwards (in a dark room). After a certain wavelength has passed (700nm), will it suddenly go dark or will I still see some violet until is slowly vanishes? (I assume the answer to this answer the question on the infrared side as well.)

The sensitivity of the eye falls off as the wavelength shortens. In the violet range of the spectrum the sensitivity of the eye only at about 50% or less. As you decrease the wavelength, sensitivity falls even further until it eventaully gets to effectively 0%. Same on the infrared side.

5. Why do we use microwaves to heat food and not infrared?

Microwaves penetrate food much more readily and I believe they are easier to generate. Infrared generally requires a hot filament or something to produce the radiation. Microwaves do not require this. (Though they have their own dangers, so don't ever start taking apart a microwave oven unless you are trained to) They also don't heat up the entire oven, just the food itself.

6. Why do microwaves cause cancer and infrared does not? (should have asked this in the bio section probably).

I don't think they do. Microwaves are not ionizing radiation and their only way of damaging tissue is through heating it to high temperatures.

 

[Helicobacter]

thx for taking the time to asnwer all of the questions

 

[sardar]

1. In the double slit experiment, the observation of what goes through the slit is accomplished through the use of electromagnetic (EM) radiation, such as photons. The electron does not completely change its direction before hitting the wall because of its wave-like nature. The electron's wave function will interfere with itself and create a pattern of constructive and destructive interference, resulting in the electron hitting the wall in a predictable location. This is known as the wave-particle duality of electrons.

2. Yes, the double slit experiment can be reproduced using photons and neutrinos instead of electrons. In fact, the original experiment was conducted with light, not electrons. The results will be similar, with the photons and neutrinos exhibiting wave-like behavior and creating an interference pattern.

3. The scale at which colors are no longer visible through an optical microscope will depend on the specific microscope and its capabilities. Generally, colors will become less and less distinguishable as the magnification increases, until they eventually appear as a uniform shade. This process is not continuous and there is a point at which the colors will simply vanish due to the limitations of the microscope's resolution.

4. As you dial the machine to produce EM radiation with shorter wavelengths, you will eventually reach a point where the radiation is in the ultraviolet range. At this point, the human eye will no longer be able to detect the radiation and it will appear as though the light has disappeared. This is because the human eye is only sensitive to a certain range of wavelengths, known as the visible spectrum. The same principle applies to the infrared side, as the human eye is not sensitive to these longer wavelengths.

5. Microwaves are used to heat food because they are able to penetrate deep into the food and cause the water molecules to vibrate, producing heat. Infrared radiation, on the other hand, is not able to penetrate as deeply and is more easily absorbed by the surface of the food. This makes microwaves more efficient for heating food.

6. The idea that microwaves cause cancer is a commonly held misconception. The truth is that microwaves, like all forms of electromagnetic radiation, are only harmful at very high levels of exposure. Infrared radiation, being a lower energy form of EM radiation, is not typically associated with harmful effects on human health. However, prolonged exposure to any form of radiation can potentially have negative effects on the body.