![]() The clock that you think is set best with respect to you will look slow to me. And it’s easy to see, from the same equations, that if you replace the′ and unprimed ones, simply change u to -u, nothing changes. Therefore, you will say my clocks are running slow. So you will say, hey, the time your clock ticked one second, I really claimed two seconds have passed. So for you, Δt’ = 1 s/√ which is more than one second. The space difference is zero because the clock is not going anywhere for me. So for me, the time difference between the two ticks will be, let’s say, one second. And let’s say it goes tick and it goes tick one more time. ![]() Or let’s take a clock that I’m carrying with me and let’s see how it looks to you. You remember that? For example, I said, take a clock that you are carrying with you. This isn’t generally, if you’ve got two events, not necessarily at the origin, then there’s spatial separation and time separation are connected in this fashion. Even this one you can think of as a formula for a difference, except one of the coordinates, or the origin. But I will write it anyway, because I will use it sometimes one way and sometimes the other way. So, differences are related the same way that coordinates themselves are. In other words, if two events are separated in space by Δx for one person and Δx’ for another person and likewise in time, then you get similar formula for differences. From this, by taking differences of two events, you can get similar equations for coordinate differences. But I remind you that if you’ve got an event that occurs at x,t for one person, and to a person moving to the right, at velocity u, the same event will have coordinates x’ = x - ut/√ and t ’ = (t - ux/C 2)/√. I won’t go over how we derive them, because I’ve done it more than once. And you guys should be really on top of those two marvelous equations, because all the stuff we are doing is a consequence of that. Professor Ramamurti Shankar: Let me remind you that everything I did so far in class came from analyzing the Lorentz transformations. Named after Professor Arthur Holly Compton (1892-1962), US physicist, who was awarded the Nobel Prize in Physics in 1927 for his discovery of Compton effect 2.Fundamentals of Physics I PHYS 200 - Lecture 14 - Introduction to the Four-VectorĬhapter 1: Recap-Consequences of the Lorentz Transformations 6 x 10 23 ), thus the Compton effect is independent of the atomic number (Z) of the absorber.Ĭompton effect becomes the dominant process when human tissues are irradiated in the 30 keV to 30 MeV energy range which is the diagnostic and therapeutic radiation range 5. An exception though is the element hydrogen, which has no neutrons in its nucleus and therefore has an electron density which is twice that of all other elements (approx. In other words, the probability of the Compton effect is dependent on the number of electrons per gram in the absorbing material, which for most elements is approximately the same (approx. Photon energy relatively constant over the range 10-600keV 1.Ītomic number (unlike photoelectric effect and pair production) Number of outer shell electrons, i.e. the electron density ![]() Thus, the energy of the scattered photon decreases with increasing scattered photon angle 5. The higher incident photon energy will cause a greater percentage loss of their energy during Compton scatter while lower energy photons will lose a smaller percentage of their energy 6. The wavelength change of the scattered photon can be determined by 0.024 (1- cos θ), where θ is scattered photon angle. The Compton effect is a partial absorption process and as the original photon has lost energy, known as Compton shift (i.e.
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