(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Parallel beam of "cold" neutrons in the x-axis, with energy 0.1eV strikes a slit system in y-z plane.

Slits are parallel to the y-axis 1 micron apart. What will be the distance between the detector at x=20m which records the highest flux of neutrons, and the closest one to it that records nearly zero flux?

2. Relevant equations

lambda = h/p

f = E/h

3. The attempt at a solution

I tried to find lambda

going with

lambda = h/p

p = gamma*m*v

v = c*(1-(K/mc^{2}+1)^{-2})^{0.5}

with K = 0.1eV = 1.602e-20 Joules

m = 1.675e-27

I found v=0... since K^{2}/mc^{2}<< 1

What am I doing wrong?

Please help...

Thank you in advance

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# Homework Help: De Broglie's Wavelength (matter wave)

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