Recent content by nousername

How do you do that? It has an x in it... Can you show me how? Thanks

Homework Statement Hey everyone. I have a mathematics exam coming up, and I am always used to checking my answers using an alternative method. We have differentiation questions and i normally check them by graphing the equation on my calc and then graphing my calculated differential equation...

hahaha lol, bad luck davo, thanks to both of you. see you around (in the forums lol)

ohhhhh, so because two gamma rays are emitted in PET it has higher resolution but since the gamma rays don't come directly from the source it has a lower contrast?

Ok, took some time to find out, but here we go. In PET, a nuclei decays to produce a positron (Beta plus decay) and this positron then collides with an electron and they annihalate each other (no idea why) to release two gamma ray photons in opposite directions. Because there are two gamma rays...

Well with spect radionuclides decay and emit single gamma ray photons and which is then detected by a gamma ray camera. PET works similarly but with two gamma ray photons, but that can't be what results in a higher contrast right? I thought the emission of more gamma ray photons resulted in a...

Homework Statement Why does SPECT produce images with higher contrast compared with its alternatives such as PET? The Attempt at a Solution I HAVE NO IDEA! I honestly researched everywhere, they only say that it has a higher contrast. I think its something to do with the hardness...

Hey everyone, Im doing this research and reading this http://science.hq.nasa.gov/kids/imagers/ems/gamma.html" it had a diagram of the depth of penetration of different wavelengths into the eaths atmosphere... my question is, How come x-rays penetrate deeper than visible light - what is the...

Hey thanks man. Do you know if the relationship of the derivative of the three graphs will change. So if i measure the derivative of each graph at some temperature (remember it's exponential) and find that one graph has a steeper slope than the other... could that change? so the other graph will...

Hey, I have this math investigation task which asks us to model the cooling of coffee in three different cups over a period of time. Anyway, i got the data, did a scatter plot and found the exponential model, but i don't know how i could determine which one has the greatest rate of cooling. I...

Hey, My book says: When an electron strikes the target metal it is attracted by the positively charged nuclei, and hence it loses speed and hence emits a photon of X-ray. That doesn't make sense to me. We learned that in centripitel acceleration, that the speed of the object being...

@A.T. hahaha, yea sorry i have test tomorrow so i can't really do much research. Thanks btw :) @phyzguy Thanks :) So how about questions 1-3?

Hey, In an X-ray tube, you know how there is the target where the electrons collide and stuff... and you know how there is the tungsten part and the the copper bit (the tungsten being the one which electrons collide on)... well my book discusses them separately and i am just a bit confused...

WOW! Thanks guys, youre awesomne. All my questions were answered!

Hey, thanks for the answer. With question 3), the X-rays get emitted when they collide with anode, wright? Not when they are being accelerated as far as i have been taught. If it is emitted while they are being accelerated, then how come they need to collide the electrons with the anode and...