Recent content by James Chase Geary

The material inside old school 3.5" floppy discs works great as a red/near-IR filter. For sun viewing you'd probably have to stack a bunch of them up, but I'm sure you could make it work.

My apologies for my lack of rigor. I wasn't trying to be misleading, just trying to get at the concept in an intuitive way. But yes, of course, the speed doesn't depend on the energy. I just meant to imply that photons were created by a some kind of process already moving at light speed.

Pedantically, photons are just light, so whatever speed they go is the speed of light. To answer the question you are asking, however, the photons are emitted with a certain amount of energy. The process which goes into the photon being created requires the energy that makes it go as fast as it...

Okay, I've got it figured out. The different angles come into play because the rod is only length-contracted in the x-direction. Because of this, the y-direction of the rigid rod in both S and S' are the same. So we can use trigonometry to get a relation between the lengths of the rods in both...

Yes, but I don't have the ability to add it on here right now. Two frames, S and S', in standard configuration (that is, with axes parallel and the motion of S' in the +x-direction, so we can use special Lorentz transformations), with the velocity v=αc in the +x-direction. The rod has one end at...

Homework Statement S and S' are in standard configuration with v=αc (0<α<1). If a rod at rest in S' makes an angle of 45o with Ox in S and 30o with O'x in S', then find α. Homework Equations We are in the world of Lorentz transformations so we have t'=(t-vx/c2)/(1-v2/c2)1/2...

New to the forum. Studied physics in undergrad before switching to a philosophy major. Realized I wasn't learning the math properly and it was too late to go back and redo it. Now I'm trying to make a better go of it on my own pace in my own time. Thanks in advance! Chase