Width Definition and 267 Threads

When calulating near resonant cross sections one usually inserts a mass width in the denominator of the propagator. This should, at least as I have understood it, correspond to taking the higher order diagrams into account. What I would like to see is a proof for the equivalence between...

The following question appeared on one of my exam papers. A CCD of pixel density 10Mpixel (1cm^-2) is used to image a component of length 10cm. Show how this does or does not meet the required accuracies of +/- 0.025mm. A similar question was asked in a previous exam where the...

Qm, infinite sq well doubles in width (reposted more clearly) Edit: posting a little clearer. I was asleep when I did this last time I don't have any notes and have to sit an exam tomorrow so i would appreciate a little help understanding this. I have the answers so i don't need them just a...

Hi again! :smile: A gardener has a rectangular vegetable garden which is 30m long and 12m wide. He traces to alleys x meters wide, similar to this: _____________________ |________| x |________| x___________ _________ |________| x |________| Determine, with x, the area occupied by...

For diffraction by a single slit, what is the effect of increasing (a) the slit width, and (b) the wavelength? It was a problem on my daughter's final and I never seemed to be able to answer it for her. :confused:

Greetings--I'm looking for data on estimates for the Higgs resonance width and I'm not quite sure where to look. I've checked the "Review of Particle Properties" and the Particle Data Group website, but I couldn't find an estimate for the higgs width. Any suggestions? Thanks, Flip

Hi, I've been trying to work this problem that someone needs for a closet project. I tried to get some help in the general math forum, but that didn't work. Hopefully I'm targeting the right group now :) Basically we're trying to build custom (cut to fit) shelves in a walk-in closet. There's...

hey guys i am kinda stumped on this problem, if anyone can give me a helping hand, it's be much appreciated, thanks! An electron is trapped in a one-dimensional infinite potential of width L. As the electron falls from the n=3 to the n=2 eigenstate, it emits a photon with a wavelength of...

A diffraction pattern is produced on a screen 140 cm from a single slit using monochromatic light of wavelength 500 nm. The distance from the center of the central maximum to the first order maximum is 3 mm. Calculate the slit width (assume first order maximum is halfway between the first and...

Waves with wavelength 2m pass through a hole in a barrier 10m wide. Compute the angular width of the central maximum. I'm not sure what I am finding here. Is it the angel between the central maximum and the 1st nodal line?...If so am I treating this like a 2 point source problem? Any help...

Need some help with this question. I think I know how to do it but I don't know the speed of sound. Could someone let me know what it is? A rifle is fired in a valley with parallel vertical walls. The echo from one wall is heard 6.0 s after the rifle was fired. The echo from the other wall is...

On average, what is the diameter of a human muscle fiber (say, a bicep muscle)?

Lets take an electron which is "in orbit" around the nucleus. As far as I know, its (ANY conceivable) wavefunction can be represented as a superposition of energy eigenfunctions, which correspond to the discrete eigenvalues of the electron's enrergy. What I do not understand is where the natural...

Hi, can anyone tell me how to estimate width of one stearic acid when it is in water. /\/\/\/\/\/\/\/\-COOH <- i want the width going up and down.

The cross-section of a tunnel is a circular arc. The maximum height of the tunnel is 10 (units). A vertical strut 9 (units) high supports the roof of the tunnel from a point 27 (units) along the ground from the side. Calculate the width of the tunnel at ground level. Please help me solve...

The size of your eardrum partially determines the upper frequency limit of your audible region, usually between 16,000 Hz and 20,000 Hz. If the wavelength is on the order of twice the diameter of the eardrum and the air temperature is 20 degrees Celcius, how wide is your eardrum? I have no...

Hi! In a non-related forum I'm trying to convince some people that the amount of dry friction has nothing to do with the size of the contact surface, just the normal force (Fn) and the friction coefficient. In this case it's about formula1, tyre width, wear and grip. I say a wider tyre...