Question. (1 Viewer)

hit patel

New Member
Joined
Mar 14, 2012
Messages
567
Gender
Male
HSC
2014
Uni Grad
2018
A magnet was dropped through a plastic tube and the magnet dropped into the hand at t=1.3s. The magnet was then dropped into an equal diameter aluminium tube and then the magnet dropped at t=2.4 s.
Part a) already explained

Now when the tube was sliced straight down through the middle and the magnet was dropped again, Explain qualitatively What would be observed and also explain why?


Note: This corresponds to faradays law of induction , back emf and lenz law but i cannot comprehend what would happen and why and how slicing the tube affects it.
 

Menomaths

Exaı̸̸̸̸̸̸̸̸lted Member
Joined
Jul 9, 2013
Messages
2,373
Gender
Male
HSC
2013
The magnet would fall through unimpeded as no eddy currents will be produced which resist the change in motion since the eddy current loops cannot be completed?
 

iBibah

Well-Known Member
Joined
Jun 13, 2012
Messages
1,374
Gender
Male
HSC
2013
The magnet would fall through unimpeded as no eddy currents will be produced which resist the change in motion since the eddy current loops cannot be completed?
Won't there still be eddy currents, they're just smaller though?
 

iBibah

Well-Known Member
Joined
Jun 13, 2012
Messages
1,374
Gender
Male
HSC
2013
No idea, lets wait for someone to clarify
lol it was a question to make you think.

The eddy currents are in fact reduced, however in terms of the hsc, we are meant to say they're so small they're negligible.
 

Menomaths

Exaı̸̸̸̸̸̸̸̸lted Member
Joined
Jul 9, 2013
Messages
2,373
Gender
Male
HSC
2013
lol it was a question to make you think.

The eddy currents are in fact reduced, however in terms of the hsc, we are meant to say they're so small they're negligible.
Can I say what I said or do I have to say the lengthy explanation they're so small they're negligible?
 

iBibah

Well-Known Member
Joined
Jun 13, 2012
Messages
1,374
Gender
Male
HSC
2013
Can I say what I said or do I have to say the lengthy explanation they're so small they're negligible?
I think it would be better to say they're negligible rather than they don't exist.
 

Menomaths

Exaı̸̸̸̸̸̸̸̸lted Member
Joined
Jul 9, 2013
Messages
2,373
Gender
Male
HSC
2013
Alright, thanks. Does this answer your question Patel?
 

hit patel

New Member
Joined
Mar 14, 2012
Messages
567
Gender
Male
HSC
2014
Uni Grad
2018
Alright, thanks. Does this answer your question Patel?
Yes thank you Menomaths, Ibibah. So the magnet would just fall through with a close time to that when the magnet falls through plastic tube. Therefore the explanation is that the eddy currents produced are minimal allowing the magnet to retain its kinetic energy?
 

Squar3root

realest nigga
Joined
Jun 10, 2012
Messages
4,985
Location
phenchod
Gender
Male
HSC
1998
Uni Grad
2005
Won't there still be eddy currents, they're just smaller though?
Yes they exist, but are much smaller as the eddy current cant form a hug loop instead like 10's of smaller ones which has negligible efffects compared to the one that has no split in it
 

Fizzy_Cyst

Well-Known Member
Joined
Jan 14, 2011
Messages
1,189
Location
Parramatta, NSW
Gender
Male
HSC
2001
Uni Grad
2005
HSC wants you to say that due to the slit, eddy currents will be minimised and no force due to the eddy currents will be experienced by the falling magnet, so it will pass out of the tube in the same amount of time as the plastic tube.

Have a look at 2011 HSC Q25 and the associated marking guidelines / notes from marking centre.

This is of course, wrong.. But, hey.. That's HSC Physics!
 

someth1ng

Retired Nov '14
Joined
Sep 18, 2010
Messages
5,558
Location
Adelaide, Australia
Gender
Male
HSC
2012
Uni Grad
2021
HSC wants you to say that due to the slit, eddy currents will be minimised and no force due to the eddy currents will be experienced by the falling magnet, so it will pass out of the tube in the same amount of time as the plastic tube.

Have a look at 2011 HSC Q25 and the associated marking guidelines / notes from marking centre.

This is of course, wrong.. But, hey.. That's HSC Physics!
This is correct.
 

Randox

Member
Joined
Sep 5, 2013
Messages
356
Gender
Male
HSC
N/A
HSC wants you to say that due to the slit, eddy currents will be minimised and no force due to the eddy currents will be experienced by the falling magnet, so it will pass out of the tube in the same amount of time as the plastic tube.

Have a look at 2011 HSC Q25 and the associated marking guidelines / notes from marking centre.

This is of course, wrong.. But, hey.. That's HSC Physics!
Lol
 

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

Top