I Dont Get This (1 Viewer)

04er

...
Joined
Jan 26, 2004
Messages
956
Location
Sydney
Gender
Male
HSC
2004
The syllabus tells us to:
Describe conduction in metals as a free movement of electrons
unimpeded by the crystal lattice

I dont see how thats even a correct statement. I thought that electrons would be unimpeded only when moving through the crystal lattice structure of a superconducting substance that is below its critical temperature. Isn't resistance in normal metals meant to be caused by crystal vibrations and thus isn't the structure impeding!? Could someone please explain this to me or at least verify the truth behind the dot point? Any suggestions would be greatly appreciated. Thanks for your time!

:)

Cheers
 

04er

...
Joined
Jan 26, 2004
Messages
956
Location
Sydney
Gender
Male
HSC
2004
why can't there be a PS_Tutor (Physics version of CM_Tutor) :(
 

Suvat

part timer
Joined
Feb 8, 2003
Messages
645
Gender
Male
HSC
N/A
Metals possess a crystal lattice structure. The sea of delocalised electrons in the metallic lattice can freely move unimpeded through the crystal lattice structure. This accounts for the high electrical and thermal conductivity of metals.

Maybe I worked my way around the dotpoint somewhat, but there are some dotpoints in both physics and chem (and prolly bio) which simply cannot be answered directly in a straightforward manner
 

04er

...
Joined
Jan 26, 2004
Messages
956
Location
Sydney
Gender
Male
HSC
2004
Thanks for your input, but I would still like someone to verify the validity of the dot point.
 

cko

Member
Joined
Mar 19, 2004
Messages
226
Location
sydney
Gender
Female
HSC
2004
Originally posted by 04er
Thanks for your input, but I would still like someone to verify the validity of the dot point.
it probly isn't... just consider it as another addition to the collection of weird ambiguous dot points that those BOS ppl prolly came up with when they wr smashd n dint bother checkn agen... but when they say "unimpeded by crystal lattice strucutre" i don't think they're using the term "unimpeded" like how they would use it when they're refering to superconductivity... just say that bcoz of the orderly arragenements of atoms in the metal structure that it makes it easier for electrons to pick out a relatively unimpeded path to travel through
 

Constip8edSkunk

Joga Bonito
Joined
Apr 15, 2003
Messages
2,397
Location
Maroubra
Gender
Male
HSC
2003
ok this was one of the controversial dotpts.... originally they had "impeded" in 2001/2 but due to supposed confusion and complaints or the efftects of hallucigents they inhaled, BOS decided last year to changed it to "unimpeded"...which is clealy wrong. I think the pt is that they are relatively unimpeded... and metals are good conductors of electricity
 

04er

...
Joined
Jan 26, 2004
Messages
956
Location
Sydney
Gender
Male
HSC
2004
Thanks you guys! I'm glad I'm not the only one who thought the dot point was retarded :D I will also ask my teacher on Monday to see what he thinks :)
 

t-i-m-m-y

Member
Joined
Nov 15, 2002
Messages
1,756
Gender
Male
HSC
2003
yeah listen to constipatedskunk:p hes smart

with regards to the dot point, think of it this way: if electrons are impeded, they will bounce off the structure etc, and the majority of them won't reach the other end (assuming its like where the +ve charge resides). when its unimpeded, then u can have electrons moving from -ve to +ve ---> therefore current

hope that makes sense
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top