braggs experiment (1 Viewer)

[batigol]

does diffraction refer to the intensity maxima and minima pattern or does it refer to the xrays actually bending around the atoms of the crystalline material when it is shone onto it? its kinda confusing because i rmb a book (jacaranda?) said it was not really reflection (as seen in many books) but diffraction, and that reflection is used for the sake of explaining the experiment.

also, does the perpendicular distance between the rays have any significance?

and when there are 2 rays, one 'reflects' off the atom in the 1st level, the other the one directly one level below it, do they interfere with each other, because the diagrams i ve seen show they continue to be parallel to one another. if so, how do they interfere???

thanks

 

[serge]

because the diagrams i ve seen show they continue to be parallel to one another. if so, how do they interfere???

thanks

yeh, not many diagrams are good at explaining
Braggs Diffraction, some show the x-rays
actually hitting the lattice and so forth
(which is completely wrong)

As i remember x-rays diffraction was good because
the xrays wavelengths were comparable to the gaps
and whatever in crystalline structures in metals
(and helped prove DNA was a double helix)

this is the first i've heard of maxima and minima
to do with Bragg's...
maxima and minima were used to explain
in Quanta to Quarks to that objects
have wave and matter-like propeties

perpendicular distance may or may not have
and effect in the formula

n(wavelength / lambda) = 2.d.sin(theta)

its only 1 short dotpoint, you dont
need to get to technical about it


If this explanation has made it worse tell me
I dont really know what you want explained?

 

[Abtari]

do we relli need to know that much for that dotpoint anyway, cos it gets relli confusing...especially with different sources claiming diff things...

i think we just need to know the Braggs' method for determining crystal structure of metals... oh yeah one thing -> in the syllabus, it says, 'outline the methods used by the Braggs'

wtf did they pluralise it? are there more than one methods to be outlined if such is asked in the exam?

HELP

 

[serge]

'outline the methods used by the Braggs'

wtf did they pluralise it?

Braggs and his son did it together

 

[Abtari]

oh shite.. shoulda made it clearer

i meant the plural 'methods' lool

 

[richz]

y do u guys go so deeply into the syllabus

 

[Abtari]

it is our bible jks

besides, how is that going 'deeply' into the syllabus... iwasnt making any philosophical prediction or anything

just wanted to know why the hell the silly bus says methods.... are they still referring to just that method in the book, but the components of it
or are there different methods the braggs used?

 

[richz]

i have not seen/heard any other methods.

http://webs.mn.catholic.edu.au/physics/emery/hsc_ideas_implementation.htm