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Author Topic: How do microwaves behave?  (Read 1649 times)

Offline hamdani yusuf

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How do microwaves behave?
« on: 07/04/2016 12:39:32 »
Basically this series of experiment is a sequel of previous experiments regarding diffraction of light, which leaves some unanswered questions. I hope from the next experiments we can build a workable model to explain the behavior of electromagnetic waves in general, and their interaction with matters.

video #1 : Introduction

In this video series we are going to investigate another form of electromagnetic wave, which is commonly called microwave. By doing so, hopefully we can get better understanding on the nature of electromagnetic wave.

A huge advantage of using microwave compared to visible light is its wavelength which is in the order of a few centimeters, which makes it convenient to manipulate. Variables obscured by the small scale of optical experiments can be easily observed and manipulated.
« Last Edit: 14/04/2016 08:23:13 by chris »


 

Offline hamdani yusuf

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Re: investigation on microwave
« Reply #1 on: 07/04/2016 12:43:21 »
this video #2 shows the microwave transmittance through several type of media.
 

Offline hamdani yusuf

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Re: investigation on microwave
« Reply #2 on: 07/04/2016 12:45:59 »
Video #3 here shows reflection of microwave by several types of media.
 

Offline hamdani yusuf

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Re: investigation on microwave
« Reply #3 on: 07/04/2016 12:54:12 »
video#4 shows a phenomenon called linear polarization which is observed in microwave transmission. Up to this point we just go with standard experimental setup usually done in school kids' physics laboratory.
 

Offline hamdani yusuf

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Re: investigation on microwave
« Reply #4 on: 07/04/2016 15:27:10 »
VIDEO#5 shows something rarely demonstrated in schools lab, which is reflection by microwave linear polarizer.
 

Offline hamdani yusuf

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Re: investigation on microwave
« Reply #5 on: 14/04/2016 06:13:25 »
In video#6, Elliptical Polarization is demonstrated using linearly polarized transmitter, a linear polarizer, and a reflector. There is also another method which is commercially used, but here we use already available components whose characteristics are individually identifiable.
 

Offline hamdani yusuf

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Re: investigation on microwave
« Reply #6 on: 14/04/2016 06:17:54 »
in video#7 we try to determine the size of photon, which is thought to be the quantum of light and all other forms of electromagnetic radiation, including microwave. We use two metal plates to create a single slit with adjustable width.
 

Offline hamdani yusuf

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Re: investigation on microwave
« Reply #7 on: 14/04/2016 07:06:31 »
Determination of "photon size" is continued in video#8, using multiple slit







Spoiler alert :
From the experiments shown in this video, it is clear that photon model is not the best way to describe microwave interaction with electrically conductive materials. We need a better model based on following facts:
-   Microwave can still pass through even when its transmission path is almost entirely covered by metal sheet. (This is found when the metal sheet is restricted so it cannot produce opposing electrical oscillation that cancel out the transmitted wave.)
-   Microwave can be completely blocked even when there are much space uncovered by conductor. (This is found when there are adequate conductors to produce opposing electrical oscillation that cancel out the transmitted wave.)
-   Maximum transmission is achieved when the Gunn diode in the transmitter is aligned with the Schottky diode in the receiver, if there is no obstacle between them.

 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #8 on: 15/04/2016 10:39:13 »
This video#9 shows a linearly polarized microwave's axis can be rotated by a sparse metal grating. It can also be turned into an elliptically polarized microwave if another sparse metal grating is added after the first.
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #9 on: 15/04/2016 10:58:53 »
In this video#10 we are investigating the power dissipated by microwave transmitter. The power used by transmitter is measured using this milli-Ampere clamp meter. It is shown that placement of a reflector can affect transmitter's power consumption.
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #10 on: 19/07/2016 11:05:32 »
youtu.be/nfYDiqiH5mU
This video shows that microwave can also experience refraction, just like normal optics.

The hardest part in making this video was molding the paraffin wax prism. But this worth the effort, since it will be used in several videos to come, which investigate total internal reflection and evanescent wave.
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #11 on: 20/07/2016 15:28:50 »
In this video #12 we are investigating total internal reflection in microwave using paraffin wax prism.

youtube.com/watch?v=vsO71mWGxKs
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #12 on: 20/07/2016 15:33:08 »

This video#13 shows a phenomenon called evanescent wave coupling. This is a continuation of previous video about total internal reflection where electromagnetic wave can't pass through the boundary between two media. Introducing additional medium beyond the boundary can make the em wave pass through the previously impenetrable boundary.
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #13 on: 20/07/2016 15:39:13 »

In this video#14 we demonstrated that placing another transparent prism in a total internal reflection can turn it into a partial internal reflection.
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #14 on: 20/07/2016 15:41:54 »

This video#15 shows that intensity received from Total Internal Reflection setup can be amplified by simply adding a metal plate behind the prism.
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #15 on: 26/07/2016 15:48:52 »
My video #16 we investigate effects of refraction to polarization state of microwave.



www.youtube.com/watch?v=ZkG-wNUGkUs

The result shows that refracted microwave retains its polarization state. No phase shift difference between s and p polarized plane.
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #16 on: 26/07/2016 15:56:15 »
www.youtube.com/watch?v=Vdny18rY8m0

This video #17 investigates effects of total internal reflection to polarization state of microwave. The result shows that total internal reflection on microwave introduce phase shift difference between s and p polarized plane, which turn linearly polarized wave into elliptically polarized wave.
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #17 on: 26/07/2016 16:01:06 »
Similar to previous video, but now we are investigating polarization in partial and amplified internal reflection.
www.youtube.com/watch?v=sd_p-pwB41U
 

Offline timey

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Re: How do microwaves behave?
« Reply #18 on: 26/07/2016 16:43:26 »
Similar to previous video, but now we are investigating polarization in partial and amplified internal reflection.
www.youtube.com/watch?v=sd_p-pwB41U
I think I'm going to have to start at the very beginning of your  YouTube experiments and watch them all in one go... I get the impression you are building up to something important that is presently evading me, and that I should pay more attention.

Do the results of your experiments lead you to a definitive hypothesis?
 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #19 on: 27/07/2016 06:00:03 »
I think I'm going to have to start at the very beginning of your  YouTube experiments and watch them all in one go... I get the impression you are building up to something important that is presently evading me, and that I should pay more attention.

Do the results of your experiments lead you to a definitive hypothesis?
Thank you for your appreciation to my work.
Yes, I had some hypotheses to explain results from widely known physics experiments. I think some aspect of currently accepted explanations are unclear or doesn't seem to fit in some phenomena that I know.
The aim of my experiments is to verify those phenomena as first hand observer, and rule out hypotheses that contradict the results.
Currently I have a hypothesis which seems potential to explain those phenomena. I already have in mind a model that can provide a mechanism to explain reflection and polarization, but still need more work to explain refraction.

 

Offline hamdani yusuf

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Re: How do microwaves behave?
« Reply #20 on: 30/08/2016 11:28:25 »
I have uploaded my latest video of my investigation on microwave's behavior. This time I demonstrate interference of microwave using two paraffin plates which act as dielectric material. Here we can see clearly the occurrence of constructive and destructive interference of the microwave due to the gap between the plates, related to microwave's wave length.

youtube.com/watch?v=2heUH1a9yYo
I think this experiment hold a key point for building my new theory on electromagnetic wave.
 

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Re: How do microwaves behave?
« Reply #20 on: 30/08/2016 11:28:25 »

 

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