Is copper a superconductor? (1 Viewer)

psychopath

Member
Joined
Jan 16, 2004
Messages
67
Gender
Male
HSC
2006
for the copper block and bar magnet question .. is copper a super conductor?? did you all write the meissner effect for when ti's cooled to -50 degrees?

cos i didnt .. i didnt think copper was a super conductor .. and so i said that the magnet falls at a much slower rate but still falls ..
 

angmor

momentica-one.deviantart.
Joined
Dec 2, 2005
Messages
560
Gender
Male
HSC
2006
thats what i thought....a lower temperature = higher resistivity doesnt it? so the induced currents dont flow as well.....were we meant to know that copper is a supoerconductor????? i dont think any superconductor has that high a critical temperature of -50 anyway
 

psychopath

Member
Joined
Jan 16, 2004
Messages
67
Gender
Male
HSC
2006
that's only in semiconductors .. but in conductors .. i.e. metals .. as temperature lowers .. vibrations int he lattice stop .. and so the resistance decreases .. it was one of the multiple choice questions ..
 

SL33pY

ceo of the banana factory
Joined
Oct 26, 2005
Messages
68
Gender
Male
HSC
2006
lower temp means LOWER resistance due to the fact that there are less electron vibrations in the lattice... am i right or wrong here?
i get the part about "is copper a superconductor?", i just went with the flow... the previous question was on super conductors.... low temps are required for superconductivity to be acheived.....
but arghhh i was confused like you on whether copper became a superconducter at -50....
meh hopefully i chose the correct way to answer this q
 

mr coolerer

New Member
Joined
Feb 21, 2006
Messages
29
Gender
Male
HSC
2006
I dont think Cu becomes a super conductor at -50 deg C, at -50 kelven would be closer to its critical frequency.

But i said that the magnet would take a greater amount of time to come to rest (land on the Cu brick) due to increased induced current.
 

angmor

momentica-one.deviantart.
Joined
Dec 2, 2005
Messages
560
Gender
Male
HSC
2006
lol do u think ill get any maks? i wrote that the electrical resistance becomes higher, but i did write that it would take a great amount of time....or is that contradicting myself?
 

SL33pY

ceo of the banana factory
Joined
Oct 26, 2005
Messages
68
Gender
Male
HSC
2006
angmor said:
lol do u think ill get any maks? i wrote that the electrical resistance becomes higher, but i did write that it would take a great amount of time....or is that contradicting myself?
contradiction = zero mista chin clearly stated that in the marking of our trials...
 

Larryman

New Member
Joined
Jul 19, 2006
Messages
17
Location
somewhere secluded from the outside world
Gender
Male
HSC
2006
mr coolerer said:
I dont think Cu becomes a super conductor at -50 deg C, at -50 kelven would be closer to its critical frequency.

But i said that the magnet would take a greater amount of time to come to rest (land on the Cu brick) due to increased induced current.
uhhh bud, there isnt such a temperature as -50 K, 0K is the minimal temperature theoretically possible. but if you didnt state that you should be fine

to be safe put the inclusion of the meissner effect within your answer and you should get full marks, even if predictions are made denying levitation, which you should of done
 

charismo

New Member
Joined
Aug 26, 2005
Messages
14
Location
sydney
Gender
Male
HSC
2006
mr coolerer said:
I dont think Cu becomes a super conductor at -50 deg C, at -50 kelven would be closer to its critical frequency.

But i said that the magnet would take a greater amount of time to come to rest (land on the Cu brick) due to increased induced current.
dude think about what you just said.. what the hell is -50 degrees kelvin??
but in other news.. i think the correct answer would've described the fact that at reduced temps, there are fewer lattice vibrations, therefore impedence to electron flow is minimised and thus magnetic field produced is stronger.. but me being the idiot i am instead discussed that copper behaves as a super conductor at -50 degrees C.. its ciritcal temp is much lower
 

angmor

momentica-one.deviantart.
Joined
Dec 2, 2005
Messages
560
Gender
Male
HSC
2006
i think that question was kinda like a trick question - i dunno for me it was coz im so conditioned to thinking in terms of semiconductors so i thought it the other way around...oh well
 

sinist4

Member
Joined
Mar 31, 2005
Messages
407
Location
*in my ipod*
Gender
Male
HSC
2006
angmor said:
i think that question was kinda like a trick question - i dunno for me it was coz im so conditioned to thinking in terms of semiconductors so i thought it the other way around...oh well
hey... i unno, buti just basically said it would fall slower than the first... the magnet would kinda 'hover' down slowly until it hits the block :S

hahaha thats wat i did ... plz tell me if that is wrong ;) thanxx >:)
 

yaseng1988

New Member
Joined
Jul 6, 2006
Messages
16
Gender
Male
HSC
2006
COPPER IS NEVER A SUPERCONDUCTOR.
I olny know 1 superconductor: YBCO
Yttrium Barium Copper Oxide.....

The rest?? who cares??
 

hamzah

New Member
Joined
Dec 17, 2005
Messages
11
Gender
Male
HSC
2006
yeah interestingly enough, copper (along with silver) are one of the few metals that never make superconductors (even at .0000000001 K). Fact of the Day for you folks.
 

*yooneek*

@UTS...I <3 Jesus
Joined
Aug 16, 2005
Messages
515
Gender
Female
HSC
2006
oh fudge lol
i was so debating over what to write cause i didnt really know if copper was a superconductor...the temp did seem a lil high... which was a clue i guess...
but ahhh well... i stuffed it and wrote the meissner effect would be observed :p
 

*yooneek*

@UTS...I <3 Jesus
Joined
Aug 16, 2005
Messages
515
Gender
Female
HSC
2006
hamzah said:
yeah interestingly enough, copper (along with silver) are one of the few metals that never make superconductors (even at .0000000001 K). Fact of the Day for you folks.
i wish i knew that before the exam :p
 

kannonland

New Member
Joined
Dec 6, 2005
Messages
1
Location
trade secret
Gender
Undisclosed
HSC
2006
The question did say PREDICT so if you say it may be super conducting and then say the magnet will float if it is super conducting?
 

hamzah

New Member
Joined
Dec 17, 2005
Messages
11
Gender
Male
HSC
2006
nah its totally wrong, they expect you to know that no such superconductor exists at -50 C. there testing if you know resistance drops with temp, due to less latice vibrations, and that the magentic field produced by the eddy current is proportional the current ( B proportional I).
 

ze.outlaw

New Member
Joined
Mar 22, 2006
Messages
4
Gender
Male
HSC
N/A
In that question I felt like it was a bit of a trick too, but as it was only a 2 marker it didn't seem like it was too hard to score full marks. I stated that the copper doesn't exhibit superconducting properties at -50C so the magnet would not levitate, but it would come to rest even more gently, due to decreased lattice vibrations in the copper at lower temperatures resulting in larger induced currents and so larger associated magnetic fields to repel the motion of the bar magnet.
Concurrence?
 

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

Top