How Do Different Materials Affect Microwave Transmission?

AI Thread Summary
Different materials exhibit varying behaviors when interacting with microwaves. An empty space allows all microwaves to pass through, while a wood frame wrapped in aluminum foil acts as a partial reflector, transmitting some microwaves and absorbing others. Solid aluminum and copper plates serve as complete reflectors, bouncing back all microwaves. Plexiglass primarily absorbs microwaves, although its thickness can influence this property. Wire mesh partially reflects microwaves due to its small openings, allowing some transmission while reflecting the rest.
stunner5000pt
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We were asked to make an educated guess of how the following would react - as transmitters, reflector, partial reflect, or absorder when a plate of the following was placed at a 45 degree angle as shown in the attachment

The transmitter transmits microwves in a straight line and the following are placed along the solid line that is drawn between. The Detectors will detect whether the microwaves are reflected or absorbed

The following were placed al9ong the solid line - Nothing, Wood frame wrapped with Aluminium foil, Solid Aluminium plate, Plexiglass, Solid Copper plate, and a Wire Mesh

Following are what i mthink may happen.

When nothing is placed then detector 1 will detect all of the microwaves that were transmitted because nothing is obsturcting the waves. Nothing will be detected at detector 2

When aluminium foil wrapped on wood frame is placed it will reflect all but since it is thin it will transmit some and the wood block with abosrb whatever is transmitted.
When a solid aluminium plate is placed it will reflect all of the light?

When plexiglass is placed it will abosrob all teh light??

When a solid copper plate is placed it iwll reflect all

When a mire mesh is placed it iwll reflect all of it ??
 

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stunner5000pt said:
We were asked to make an educated guess of how the following would react - as transmitters, reflector, partial reflect, or absorder when a plate of the following was placed at a 45 degree angle as shown in the attachment

The transmitter transmits microwves in a straight line and the following are placed along the solid line that is drawn between. The Detectors will detect whether the microwaves are reflected or absorbed

The following were placed al9ong the solid line - Nothing, Wood frame wrapped with Aluminium foil, Solid Aluminium plate, Plexiglass, Solid Copper plate, and a Wire Mesh

Following are what i mthink may happen.

When nothing is placed then detector 1 will detect all of the microwaves that were transmitted because nothing is obsturcting the waves. Nothing will be detected at detector 2

When aluminium foil wrapped on wood frame is placed it will reflect all but since it is thin it will transmit some and the wood block with abosrb whatever is transmitted.
In fact, it will transmit most of the waves if it is thin compared to the wavelength. Typical aluminum foil is less than 1mm thick, and the microwave wavelength is about 12 cm. So, most of the energy will be transmitted through the foil and absorbed by the wood. A little bit will be reflected.

When a solid aluminium plate is placed it will reflect all of the light?

When plexiglass is placed it will abosrob all teh light??
Depending on the thickness, but I think this is mostly right. Thin plexiglass will transmit some too.

When a solid copper plate is placed it iwll reflect all

When a mire mesh is placed it iwll reflect all of it ??

I think you've got it all.
 


Your educated guesses on the reactions of the different materials as transmitters, reflectors, partial reflectors, or absorbers are mostly correct. Here is a breakdown of each material's possible reaction:

- Nothing: As you mentioned, nothing will be detected at detector 2 because the microwaves are not being obstructed in any way.

- Wood frame wrapped with Aluminium foil: This is a partial reflector. The thin aluminium foil will reflect some of the microwaves, but some will also pass through and be absorbed by the wood frame.

- Solid Aluminium plate: This is a reflector. As you guessed, it will reflect all of the microwaves.

- Plexiglass: This is an absorber. The plexiglass will absorb all of the microwaves that come into contact with it.

- Solid Copper plate: This is also a reflector. Just like the solid aluminium plate, it will reflect all of the microwaves.

- Wire Mesh: This is a partial reflector. The small holes in the wire mesh will allow some of the microwaves to pass through, while the rest will be reflected.

Overall, your understanding of how different materials can behave as transmitters, reflectors, or absorbers is correct. Keep in mind that these are just educated guesses and the actual reactions may vary depending on the specific properties of each material and the angle at which they are placed. It would be interesting to conduct an experiment to see how your guesses compare to the actual results. Good job!
 
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