A monochromated beam of neutrons (speed 0.40 m/s) is directed through a double slit with 1.0 mm separation. An array of detectors is placed 10m from the slit.(adsbygoogle = window.adsbygoogle || []).push({});

a)what is the de Broglie wavelength of the neutrons?

b)how far off-axis is the first zero-intensity point on the detector array?

c)explain why we cannot measure which slit a neutron passed through while forming a diffraction pattern.

for a) i used lambda= h/p and came up with 9.89*10^-7. i hope this is right.

the rest of the question is a problem. i am lost. the only equations i can find are Dsin(theta) =nlambda (given by my proff) and Dsin(theta)= lambda/2. i know that i can't just use either of these equations on their own, but i am baffled as to what i should use. i'm not looking for anyone to pretty much do the question, i just need a nudge in the right direction and hopefully a simple explanation as to what is actually going on in this situation, and what the question is asking. thanks

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# Homework Help: Double slit electron experiment

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