Recent content by DGriffiths

Thanks folks for your insight really appreciate it.

this example was in a book I bought ( maths methods for physics, Mathews and Walker) dy/dx + sqrt( (1-y^2) / (1-x^2) ) = 0 dy/(1-y^2) + dx/(1-x^2) = 0 sin -1 y + sin -1 x = c [1] or, taking the sine of both sides x (1-y^2)^1/2 + y...

Ah Professor Walter Lewin love him, thanks DevilsAvocado never seen that video before though.

I think if the electron is not being 'watched' as it passes through the slits then no particular path is indistinguishable from any other path - in this case you add the quantum amplitudes of the individual paths before you take the modulus squared of the quantum amplitudes (that equates to the...

Thanks for all the replies folks, I didn't think about the ability to see a nice diffraction pattern being dependent on the correct lambda/d but that makes sense to me so cheers

I am interested to know why in any description of electron diffraction apparatus they seem to suggest that the electrons need accelerating up to 5kV (or at least several kV) to show the electron diffraction rings, this seems to give a de Broglie wavelength of around 1.2 x 10^-11m whereas the...

Thanks very much for all replies - I'd only heard of Kirchoff in respect to electrical circuits. I get the "emissivity = 1 - reflectivity. More reflectivity = less emissivity." if that's what the law says but I still don't get why? Is there any mental picture (even if not totally accurate) that...

I've seen much mention in websites of matt black surfaces being better emitters of infra red than shiny silver ones so if a matt black and shiny silver surface are heated to about 100 deg C the black one will cool down more quickly as a result of this! Doesn't Wien's law state that the amount of...