Forms of electromagnetic radiation

[idlewild]

If the forms of electromagnetic radiation only differ in their wavelengths, then how is it that when a light wave's length increases it remains classified as a light wave and not a microwave or a radio wave? What am I missing? I'm confused! <div class="Discussion_UserSignature"> </div>

 

[drwayne]

I think you are making too much of labels, if I am understanding your question correctly...<br /><br />Labels like infrared, visible, ultraviolet, xrays etc. are just that, labels that define electromagnetic radiation of certain wavelengths - they are just that, convenient lables that define regions of the electromagnetic wavelength spectrum.<br /><br />Wayne<br /><br /> <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[derekmcd]

Might you be referring to doppler effects and redshift? If so, the way I understand it is that the change in frequency is but an illusion (albiet a measureable one). The actual source the light is being emitted is not altered. I don't think the radiative effect on matter that the wave interacts with will change based on its red/blue shift. <br /><br />If we know the source is emitting UV radiation, only then can we determine the redshift value. <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[MeteorWayne]

No, I think he means all the different names for the frequencies of the electromagnetic spectrum.<br /><br />The only reason we consider light different than all the rest is that we have built in receivers/decoders built into our head <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[heyscottie]

And if you do shift visible light far enough, we'll start to call it something besides visible light. Most commonly, you'll find red light get shifted into the infrared spectrum, or blue light get shifted into ultraviolets.

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>If the forms of electromagnetic radiation only differ in their wavelengths, then how is it that when a light wave's length increases it remains classified as a light wave and not a microwave or a radio wave? What am I missing? I'm confused!<p><hr /></p></p></blockquote><br /><br />One big factor is that in the early days of electromagnetic research (when these terms were being coined) people did not realize that they were actually all the same thing. There are some other confusing terms that arose from the same problem. For instance, there are alpha, beta, and gamma radiation. You'd think they were all various energies of the same radiation, right? So did the guy who came up with the names, but he was wrong. Alpha and beta radiation are particles (protons and electrons), and gamma radiation is really high frequency electromagnetic radiation (invisible light -- high energy x-rays, actually). <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[lukman]

How about electromagnet at the pole, are they high energy too or particle? because they are so powerfull and block most of the high energy radiation from the sun. <div class="Discussion_UserSignature"> </div>

 

[CalliArcale]

The Earth's magnetic field redirects the Sun's particle radiation (such as alpha and beta particles); it doesn't exactly shield it. Some of it will break around the Earth's magnetosphere, like water breaking around the bow of a ship. But some of it does end up travelling down the magnetic field lines until it collides with particles in our atmosphere, ionizing them. This is what produces the aurora. In sufficient quantities, this ionizing process can also produce electromagnetic interference, sufficient to disrupt radio communications or even overload and burn out circuitry. These days, electrical companies pay very close attention to the space weather forecast.<br /><br />The molecules of our atmosphere block a lot of the high energy electromagnetic radiation, such as gamma rays. (And famously, the ozone layer blocks a significant amount of the ultraviolet radiation.) It has its limits (a sufficiently large burst will make it through) but because it shields us so well, if astronomers want to do x-ray astronomy or study gamma ray bursts, they generally have to do it with either space telescopes or airplane-mounted telescopes. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[Mee_n_Mac]

<font color="yellow">...how is it that when a light wave's length increases it remains classified as a light wave and not a microwave or a radio wave? </font><br /><br />Just in case you're still confused .... we do call (or classify) light that has been redshifted (had it's wafvelength increased) as microwaves or radio waves. One example it the Cosmic Microwave Background Radiation (CMBR). It's received as microwaves and called such but it believed to be light from the early universe.<br /><br /> <div class="Discussion_UserSignature"> <p>-----------------------------------------------------</p><p><font color="#ff0000">Ask not what your Forum Software can do do on you,</font></p><p><font color="#ff0000">Ask it to, please for the love of all that's Holy, <strong>STOP</strong> !</font></p> </div>

 

[vandivx]

maybe more precise answer might be that visible light makes up fairly broad spectrum and 'normally' doesn't shift too far to get totally out of the visible light range<br /><br />even those frequences near the limit of light spectrum don't get all shifted out beyond the visible spectrum<br /><br />don't expect velocity redshift due to even most speeding car make you see red while looking behind you and blue looking forward <img src="/images/icons/wink.gif" /><br /><br />vanDivX <div class="Discussion_UserSignature"> </div>

 

[idlewild]

I was still confused so thank you for your reply. It was to the point. Thanks again! <div class="Discussion_UserSignature"> </div>

 

[idlewild]

Your answer was also very helpful. Now I understand! Thanks. <div class="Discussion_UserSignature"> </div>

 

[nexium]

Earth's magnetic field is too weak to bend light or other electro magnetic radiation, but it does steer ions and electrons. The polar regions have somewhat less electromagnetic radiation than the rest of Earth, because the Sun is always close to or below the horizon, making the average path though the atmosphere longer. The high speed ions do however produce some electromagnetic radiation as they react with the air atoms and skin atoms. Neil