# Recent content by godtripp

1. ### Calculate Accuracy of GPS?

Hello, I need to calculate how accurate a GPS system is using only Special Relativity and a very basic knowledge of GR (without tensors...which is limited). I'm not sure where to begin however... where does the uncertainty in the measurement come from? How can I calculate the size of the...
2. ### Special Relativity - Help Please!

The 7 years is as measured by the traveling twin's frame. So my intuition wants to say that his return is 14 years in his frame. However I think that this may be flawed due to lorentz contraction of the distance being traveled.
3. ### Special Relativity - Help Please!

Homework Statement Two twins start their clocks at the same time, one of them travels for 7 years at a speed of 4/5c, reverses direction and returns at half the speed. The other twin remains stationary, what is the difference in their age? Homework Equations t = t_p γ The Attempt...

5. ### Compton Scattering Concept Question

Hi, I had an issue with compton scattering that I never received a satisfactory answer for. My issue was that after the collision, there exists a y component of momentum... but all diagrams of the compton effect align the axis center to center from the photon to the electron and on top of...

Thank you!
7. ### Infinite Series

Thank you micromass, I'll try expanding that out as soon as I get home. I'm sure it'll telescope out... there is one thing driving me nuts however. \sum 1/n is a harmonic series... which is divergent. I'm not sure about \sum 1/(n+k) since series have the property that \sum (a-b)=\sum...
8. ### Infinite Series

\sum\frac{1}{n(n+k)} from n=1 to infinity find that the series is convergent and find it's sum. Now I'm a bit confused... I can show it's convergent with k=1 and I attempted the same thing with k by breaking this into partial fractions. But I'm given a harmonic series that is divergent...
9. ### Whether the boy can catch the ship? relative velocity

Direction should affect your time traveled by the boy, and thus your velocity of the boat. Maybe you found a way the angles cancel out to an identity? I'm not sure I'm just considering the problem in my head.
10. ### Shopping Carts, Finding Horizontal Force

This problem is easier if you rotate your axis 13 degrees. So draw the x axis to be parallel with the acceleration. With your current axis ... Fx = F and don't forget your normal force and force due to gravity. Now, if you redraw your axis along the direction of acceleration Fx = Fcos(13)...
11. ### Whether the boy can catch the ship? relative velocity

Hmmm, since it doesnt say anything about the boy's direction when he starts swimming I assume they want you to consider a right triangle...of course this depends on your level of physics class also... if you find this is not the case then use the law of cosines to solve the problem . Consider a...
12. ### Finding Lorentz Vector? -Physics Noob

Thank you so much tim. I was thinking of the angle from psuedorapidity in terms of the Pz vector component and not of the total momentum! Thanks!
13. ### Finding Lorentz Vector? -Physics Noob

I was given this as an extra-curricular activity... way over my understanding of physics, sophmore year undergraduate. But I can use a bit of help. I'm given data from a collision resulting in 2 muons. (this is exactly how the text is written to me, if any of these definitions are not...
14. ### Mass reconstruction

sorry, I'm going to have to verify in layman's terms.. this is way above my current education in physics. (sophmore year undergrad) So what you're doing is analyzing the decay products, summing up their total energies to trace back the energy , and thus the masses, of their parent particles?
15. ### Mass reconstruction

What is it? I always hear it and never know what exactly it means to "reconstruct" mass.