# Frequency vs objects

Discussion in 'General Electronics Chat' started by cjdelphi, Jan 26, 2011.

1. ### cjdelphi Thread Starter New Member

Mar 26, 2009
272
2
For example, a frequency which has a wavelength of say 10 meters and a frequency of 1 meter... take a wooden door which is 5 meters by 5 meters, funny looking door I know but...

[question 1]
Take a house, you have bricks on both sides of the funny 5x5m door, the 1 meter wavelength will happily go through the door because the wavelength is shorter than the door, but when it does go through the door I'm right in assuming the amplitude/power will drop because the door will absorb some of the energy?

[question 2]
Now the 10m wave comes along, the wave is longer/wider than the door so the wave will not pass... but why? can't the wave travel through the bricks on either side and the door (walls+door > 10 meter)

Or does the wave pass? partly through the wall and partly through the door? all I can imagine really is a piece of string, as the string passes through the wall/door part of the energy (thickness) gets reduced... is there a better way of understanding this concept?

[And last but not least..]
5x5 door the 1 meter wave will pass through, because it's wavelength is less or equal to the 5x5m door, microwaves are a few inches in length and on the front of your microwave there's a wire mesh with small holes in, the idea being light is of microscopic wavelength so it passes the light through keeping the microwaves from passing...

But... this is the most confusing part, visible light waves of the EM spectrum are very very short indeed, so why don't they pass through a door? like a radio wave does?

2. ### Kermit2 AAC Fanatic!

Feb 5, 2010
3,852
968
Once you leave the low energy Radio band of the EM spectrum the radiation begins to behave more and more like particle radiation.

For lack of a better term, its rate of interaction with the macroworld you and I inhabit cause it to have different affects on different types of matter. Matter is mostly empty space, very little of the area you would classify as an atom actually has 'something' physically there.