Homework Statement
The deuteron ground state is made up of l = 0 and l = 2 states;
a)Show this mixture cannot be an eigenstate of a central potential Hamiltonian
b)Using first-order time independent perturbation theory, argue the potential must contain a term proportional to some combination of...
Ah I see! So for radiation the pressure = energy density / 3? That simple? :D
Hmm I see, so for example, if I assume it's matter dominated, would I just assume that the ageof those stars = the age of that universe? If so;
H = 2/3t , and using 19 billion for t?
Thanks a lot for your help...
Homework Statement
Estimate the pressure of the CMB photons today. [You will need to choose a reasonable value for the present value of the temperature of the CMB. The radiation
constant is α = 7.56 × 10−15erg cm−3K−4
Assume that a new population of stars is discovered, and their age is...
But I only added that D as the distance to the plane right at the end :(, and by that D i simply mean
(D^2 =(x-a)^2 + (y -b)^2 +(z-c)^2) , have edited it now though..
Could you give me any hints as to why yours is different? :( To get so the D from the value of L, i simply put L back into the...
URGENT - Lagrange Multipliers
Homework Statement
:confused:
Using the method of lagrange multipliers prove the formula for the distance from a point (a,b,c) to a plane Ax + By + Cz = DThe Attempt at a Solution
Using the equation of the form;
H(x,y,z,L) = (x-a)^2 + (y -b)^2 +(z-c)^2 + L(Ax...
Well I'm just considering a simple series RLC circuit.
Because the impedances of the capacitor and inductor cancel due to their phase difference, it's actually possible for the impedance of the capacitor to be greater than the overall impedance of the circuit. And since the V through the...
Hey there,
I've been learning about AC circuits recently and while considering and LCR circuit it occurred to me; it's possible for the voltage drop across a capacitor/inductor/both to be greater than the voltage source itself however I can't think of the reason for this, any hints or reasons...
Ah I've gotcha, I guess I was getting confused as I wasn't confident in the maths and I carried on thinking about the argument you outlined.
Thanks a lot for the help!
Homework Statement
A Loop of height L and initial width X is placed in a magnetic field and the plane of the loop is perpendicular to the field, the loop is connected to a light bulb of resistance R. By applying a force F to the left hand side of the loop it can be compressed at a constant rate...
Thank you very much for the quick replies;
Of course I realize that limiting my options to those 3 institutions would be foolish, and i'd certainly be more than happy to consider a good PhD program anywhere in a subject that interests me, I was simply asking for clarification.
Thanks very...
Hey there,
I'm still at undergraduate level studying Physics right now, but looking ahead at the possibility of pursuing a PhD I'm slightly worried about what some people are saying.
I'm currently studying at quite a good university, but seeing as I wanted to do a year abroad to learn a...
Homework Statement
A beam of 50eV electrons travel towards a slit of width 6 micro metres. The diffraction pattern is observed on a screen 2m away.
Use the angular spread of the central diffraction pattern (+/- lambda / slit width) to estimate the uncertainty in the y-component of momentum...