Recent content by Isaac Pepper

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    Atomic Physics - Orbital Angular Momentum Probability

    Working through the numbers, I have got an answer of $$c_{1,0}=0$$ $$c_{1,1}=-\frac{1}{\sqrt{2}}$$ and $$c_{1,-1}=\frac{1}{\sqrt{2}}$$ Which means the answer to i. is 1/2, ii. is 1/2+1/2 = 1 But how do I calculate the probability of measuring Lz=0? The probability of m=1 AND l =1 was 1/2 (from...
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    Atomic Physics - Orbital Angular Momentum Probability

    Sorry! Edited my post, it was meant to be 2ħ2. I am having trouble understanding the integral though... What are Yl,m... and dΩ :( I have a table with values of Y0,0, Y1,0, Y1,1 etc... So for example $$Y_{0,0} = \sqrt{\frac{1}{4 \pi}}$$ $$c_{0,0} = \int \sqrt{\frac{1}{4 \pi}} \sqrt{\frac{3}{4...
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    Atomic Physics - Orbital Angular Momentum Probability

    Homework Statement Consider an electron in a state described by angular wavefunction $$\psi(\theta,\phi)=\sqrt{\frac{3}{4 \pi}}\sin \theta \cos \phi$$ Here θ and φ are the polar and azimuthal angles, respectively, in the spherical coordinate system. i. Calculate the probability that a...
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    OPERA experiment - Special Relativity

    Yeah, that seems to my solution too, though I divided it by ##c^2## so my answer was $$\frac{28GeV}{(3*10^8)^2}*i*7.06*10^{-3}=i*2.20*10^{-18} GeV/c^2$$
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    OPERA experiment - Special Relativity

    Fair enough, I know the calculations I did after it were wrong though, so ignore them, I'm sure you have the right answer ! I will look through what I have done in the morning to try and work it out. Thank you for all your help, both of you !
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    OPERA experiment - Special Relativity

    If the neutrino arrived ##60.7*10^{-9}s## before light would, then ##t_2-t_1=\frac{d}{v}-\frac{d}{c}=-60.7*10^{-9}s## In which case ##t_2-t_1+\frac{d}{c}=\frac{d}{v}## $$v=\frac{d}{t_2-t_1+\frac{d}{c}}=\frac{731*10^3}{-60.7*10^{-9}+\frac{731*10^3}{3*10^8}} = 300 007 473.5 m.s^{-1}$$ Atleast...
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    OPERA experiment - Special Relativity

    Do you mean for part (b) ? I have done $$v=c\sqrt{1-\frac{m^2c^4}{E^2}}$$ $$v^2=c^2-\frac{m^2c^6}{E^2}$$ $$m^2=\frac{E^2(c^2-v^2)}{c^6}$$ $$m=\frac{1}{c^2}\sqrt{E^2-\frac{E^2v^2}{c^2}}$$ Plugged in numbers and got ...
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    OPERA experiment - Special Relativity

    Ok, even then I'm not sure how to differentiate this expression with respect to p I can re-arrange to get ##E=\sqrt{m^2c^2+p^2c^2}## but I don't know how to differentiate that wrt p
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    OPERA experiment - Special Relativity

    I do understand that, which is partly why I don't understand what the question is asking me... Any ideas on how to solve this? I don't even understand how to do part (a) at this point
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    OPERA experiment - Special Relativity

    Any help would be greatly appreciated, I'm still stuck on the question. Sorry for the double post.
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    OPERA experiment - Special Relativity

    Homework Statement In 2011, researchers at the OPERA experiment thought they had seen neutrinos with mass m and energy E = 28 GeV moving faster than light. The baseline between the source and the detector was 731 km, and the neutrinos seemed to arrive 60.7 ns early, compared to the maximum...
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    Special Relativity - time dilation and length contraction

    Is it simply ##x'=\frac{x}{\gamma}=\frac{9.3*10^{20}}{1*10^{12}}=9.3*10^{8}m = 3*10^{-8} pc## then? In which case (c) would also simply be ##t=\frac{t'}{\gamma} = \frac{(3.1*10^{12}+1.55*10^{-12})}{1*10^{12}} ≈ 3.1 s## ? Doesn't seem right to me.. EDIT ...
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    Special Relativity - time dilation and length contraction

    Homework Statement The highest energy protons have gamma factors around ##1.0*10^{12}##. (a) Our galaxy has a disk diameter of 30 kpc, which is ##9.3*10^{20}m##. If a photon and one of these high energy protons start traversing the galaxy at the same time, by how long will the arrival of the...
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    Muon special relativity problem,

    I follow the reasoning for this. The radioactive decay equation gives us ##N=N_0e^{\frac{-t'}{t_0}} \rightarrow t'=2.21*10^{-8}s## This is the time in the rest frame of the muon. Then using the Lorentz transformations : ##t = \gamma t'## ##v=\frac{d}{t} \rightarrow v=\frac{d}{\gamma t'}## How...
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    Relativity - Fast and slow moving objects

    ##\gamma mc^2-mc^2 = \frac{1}{2}mv^2 \rightarrow \gamma mc^2 -mc^2=\frac{1}{2}m\beta^2c^2## where ##\gamma = \frac{1}{2}\beta^2+1## Therefore ##\frac{1}{2}\beta^2=\gamma-1## Which means that $$\frac{1}{2}mv^2=\frac{1}{2}m\beta^2c^2=mc^2(\gamma-1)$$ $$\gamma mc^2-mc^2 = mc^2(\gamma-1)$$ Is that...
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