Ray Definition and 517 Threads

How does a CRT focus an electron beam? I get the basics of it. But I'm a little confused on the details. For electric focusing, how does accelerating the electrons cause it to focus? I'm looking for a more mathematical treatment of the subject. Everything I've found is just descriptive...

If you're on the east coast, Ray Brardbury's on Neil Cavuto's "Your World" REAL SOON. Incase you don't know, it's on Fox News. Expect some Michael Moore bashing, as Bradbury got pissed Moore ripped off his book title. Should be fun regardless.

A Fe (57) atom is in an excited state 14.4 keV above the ground state. The nucleus decays to the ground state with the emission of a gamm ray. What's the recoil speed of the nucleus? I'm not sure how to set this up. I thought a photon would have no mass, therefor no momentum. If so I...

1. If a light ray go through a boundary of air and glass(i.e. angle of incidence is 90 degree), Is there any refraction or reflection? 2. If angle of incidence is 0 degree( the light ray is normal to a glass), Is there any reflection? 3. Suppose the situation is same as (2), but the light ray...

I was just thinking, nuclear fusion in the core of a star produces a gamma ray burst that takes about one million years to reach the surface of the star where it becomes visible light. Why does it take the gamma ray one million years to reach the surface if it is traveling at light speed? I...

Would a quark-gluon plasma reflect x rays and gamma rays and would such a plasma exist in gamma ray bursters and black holes?

What causes the short-lived, highly energetic, flash of light emitted by some black holes as they are created?

Hi...Juz curious. I was doing the prism experiment yesterday and was just curious about how the white ray of light changes to a spectrum of colours... Has it got anything to do with the change in the speed of the different colours of light, the frequency / the wavelength? Or just purely...

Thank-you for taking the time to read my problem. I am currently doing work with light and boundaries and have come across a question that I am having a hard time understanding. I know how to calculate angles when they go through one boundry but I can not figure out how to do it when there is 2...

Ok, a lens is held upright with a piece of clay. In front of it is a bulb, and behind it is a screen at the location of the image of the bulb. Now, what would happen to the image if the top half of the lens were covered by a mask? And what if the mask had a small hole in the center and were...

Hey guys In a few days i will be doing an Assessment task requiring me to do a number of things relating to experiments on Motors and Generators and Cathode Rays.. I am confident in doing all of it but the last part states we have to analyse secondary information to carry out a risk...

what kind of equipment do we need to detect cosmic rays? can i build something to detect fairly high energy cosmic rays in my basement?

{copyrighted material deleted by Phobos - please check out the link instead} Reference: http://www.sltrib.com/2004/Jan/01132004/utah/128616.asp

Does anyone know the peak(or the energy at which the flux is the greatest) of the GCR spectrum? And a quotable source for that. I am pretty sure it is in the 1-10 GeV/nucleon range. thanks

This Paper may be large, but it is a must for some pretty far reaching consequences for Cosmology. http://uk.arxiv.org/PS_cache/astro-ph/pdf/0312/0312347.pdf I will astounded if the paper is not seen in the near future as a remarkable paper of astronomical foresight and will be a paper...

It's embarassing to have to ask this, but I have never seen this issue discussed. Is there an upper limit on the energy of the gamma rays from the gamma ray bursts? Namely 1.022 MeV? Because any gamma ray of that energy or greater can and will produce pairs of electrons and positrons by...

Here is the problem: A glass sphere with a diameter of 5cm has a scratch on its surface. When the scratch is viewed through the glass from a position directly opposite, where is the virtual image of the scratch, and its magnification? The glass has an index of refraction n=1.50. Explain the...