Recent content by richard7893

∫exp(-x^2/k) *cos(2*pi*s*x) dx from -infinity to infinity So this integral is an error function unless I take the definite integral from -infinity to infinity. Will this give me a pretty answer in I do this with the limits specified?

Homework Statement Assume a transmission imaging system with the following parameters: focal spot PSF equal to a Gaussian with FWHM = 0.5 mm, a detector PSF equal to a Gaussian with FWHM = 0.1 mm, source-to-detector distance = 100 cm. Compute: 1. the optimal source-to-object distance 2...

Homework Statement Pro #2 if you click on this link. http://s1104.photobucket.com/albums/h332/richard78931/?action=view&current=hw4.jpg Homework Equations , The Attempt at a Solution Click here http://s1104.photobucket.com/albums/h332/richard78931/?action=view&current=2a.jpg...

http://s22.photobucket.com/albums/b317/richard7893/?action=view&current=emag.jpg" This is what I have so far if you click on the link. Can I cancel out the r^2 terms in the differential? Or do I distribute the r^2 in the numerator and then perform the differential? How can I insert a dirac...

the formula for obtaing rho goes thru this eqn: del dot E = rho/epsilon-not Del dot E in sperical coords. is : (1/r^2) d/dr [ r^2 V(r)] (the (1/r^2) and r^2 are built into the formula.) once i did this multipled both sides by epsioln-not to obtain rho. This question is from Grifiths...

Homework Statement the electric potential of some configuration of charge is given by the expression: V(r)= (Ae^(-pr))/(r) where A and p are constants. Find the E-field E(r), the charge density rho(r) and total charge Q. The answer for rho is given in book as: epsilon-not * A *...

I think what you wrote makes sense. When we use the pythagorean thm in part a) to find the total lenth observed is S we assume the "y component" of length remains unchenged from the moving frame to stationary frame, this is why we use sin30 in the pythagorean. however the angle from which S'...

Homework Statement A meter stick at rest in S' is tilted at an angle of 30 degrees to the x'axis. If S' moves a speed beta = 0.8 with respect to S. a)How long is the the meter stick as measured in S ? b)What angle does it make with the x-axis? Homework Equations l=l naught/gamma The...

Is the bar still at a 60 degree angle as seen in the unmoving frame?

I mean find the eigenvectors of each matrix. The original question is Find the eigenvals and eigenvecs of A=[1,0;0,9]. I know the eigvals are 1 and 9. However when I try to find the eigvec for lamda =1 and lamda = 9 respectively i get these matrices: when lamda =1 [0,0;0,8] and lamda...

Homework Statement im trying to find the eigen vector for these 2 matrices: A=[0,0;0,8] AND A=[-8,0;0,0] Homework Equations The Attempt at a Solution BACICALLY WHAT IM DOING IS "GUESSING" AT What x1, is then I am coming up wth the solution to x2 once I've made my guess for x1. how...

Homework Statement If the gravitational field vector g inside a sphere is independent of the distance from the center of the sphere r, how does the density ρ(r) of the sphere vary as a function of r? Homework Equations gauss' law for gravity: integrate g*da=4*pi*G integrate ρ(r) dv...

I am not understanding why the potential energy (U) for a magnetic dipole is at it's maximum when the magnetic dipole moment is antiparallel to the magnetic field (B), why U is at it's minimum when the magnetic dipole moment and B are parallel, and why U is zero when B and the magnetic dipole...

will the current carrying wire experience a force from the magnetic field it produces?... no right?

For Torque of current carrying wire in magnetic field why does the magnetic field of the current carrying wire itself not contribute to torque?