While it is true that the "standard" bar magnet does have a north and south end, the magnets (at least the ones from Kelvin) are magnetized through the face of the magnet. To demonstrate this, if you take two of the rectangular magnets sold by Kelvin and connect them so that they form the longest possible magnet (i.e. short sides touching) and then merely rotate one of the magnets about the axis going down the length of the two of them, it will suddenly be repelled. This is so even though no end-to-end flipping has been performed. This means that laying two rows of magnets with all of the North sides facing up is easy.chalker wrote: 2. Bar magnets. Since one end is N and the other is S, if you get a long enough bar magnet you can just use them like railroad ties. Obviously 'flipping them over' won't do anything since they are standard bar magnets. If you want to have the same polarity, you need to get shorted bar magnets and put 2 per row (but technically then you actually have 4 magnetic rails (N-S-S-N).
MagLev C
-
- Member
- Posts: 142
- Joined: Thu Dec 27, 2012 12:56 pm
- Division: C
- State: GA
- Has thanked: 0
- Been thanked: 0
Re: MagLev C
-
- Member
- Posts: 88
- Joined: Thu Jan 31, 2013 2:04 pm
- Division: C
- State: CO
- Has thanked: 0
- Been thanked: 0
Re: MagLev C
Rule 3, i. prohibits integrated circuits.
Is that just ICs or did they mean all semi-conductors?
Is that just ICs or did they mean all semi-conductors?
--
Poudre High School, Fort Collins CO.
Poudre High School, Fort Collins CO.
-
- Coach
- Posts: 1318
- Joined: Thu Nov 13, 2008 3:01 am
- Division: C
- State: CO
- Has thanked: 0
- Been thanked: 3 times
Re: MagLev C
Purely personal opinion- usual caveats, "only official place for clarifications is..."erikb wrote:Rule 3, i. prohibits integrated circuits.
Is that just ICs or did they mean all semi-conductors?
1) IC mention is in conjunction with brushless motors (which require fairly complex ICs to work)
2) there is no language addressing/mentioning/allowing/prohibiting other electrical/electronic components
3) definition of IC is multiple, integrated, circuits
4) a single semi-conductor is not an IC
5) multiple semi-conductors, unless 'integrated' onto some sort of....substrate do not constitute an "IC."
Len Joeris
Fort Collins, CO
Fort Collins, CO
-
- Member
- Posts: 169
- Joined: Thu May 19, 2011 6:00 pm
- Division: Grad
- State: PA
- Has thanked: 0
- Been thanked: 0
Re: MagLev C
I agree with balsa's interpretation (that's all it is though, a interpretation). A event supervisor could rule else-wise without the necessary clarification from soinc.Balsa Man wrote:Purely personal opinion- usual caveats, "only official place for clarifications is..."erikb wrote:Rule 3, i. prohibits integrated circuits.
Is that just ICs or did they mean all semi-conductors?
1) IC mention is in conjunction with brushless motors (which require fairly complex ICs to work)
2) there is no language addressing/mentioning/allowing/prohibiting other electrical/electronic components
3) definition of IC is multiple, integrated, circuits
4) a single semi-conductor is not an IC
5) multiple semi-conductors, unless 'integrated' onto some sort of....substrate do not constitute an "IC."
Harriton Class of 2013
Vice-Deputy of Avionics and Control for Lunar Lion
Assistant Coach of State College High School
Vice-Deputy of Avionics and Control for Lunar Lion
Assistant Coach of State College High School
-
- Member
- Posts: 1
- Joined: Thu Nov 21, 2013 9:35 pm
- Division: C
- State: NH
- Has thanked: 0
- Been thanked: 0
Re: MagLev C
Has anyone been able to get their maglev to levitate without touching the side rails AT ALL? I have exhausted a great deal of effort to solve this problem and I have made very little progress towards a perfectly levitated train.
-
- Administrator
- Posts: 393
- Joined: Wed Mar 02, 2011 7:10 pm
- Division: Grad
- State: KS
- Pronouns: He/Him/His
- Has thanked: 0
- Been thanked: 14 times
Re: MagLev C
As mentioned before on this thread, Earnshaw's theorem appears to prohibit this.sodiumgood wrote:Has anyone been able to get their maglev to levitate without touching the side rails AT ALL? I have exhausted a great deal of effort to solve this problem and I have made very little progress towards a perfectly levitated train.
-
- Member
- Posts: 96
- Joined: Tue Dec 27, 2011 12:32 pm
- Division: Grad
- State: MN
- Has thanked: 0
- Been thanked: 0
Re: MagLev C
Unless you have magnets on the sides of the track and the car, touching the side rails is pretty much unavoidable. Assuming you're not trying side magnets, as long as your car's width is just under the track width, touching the sides won't matter much and it'll go down the track just fine. You could then also try lining the sides with low friction material or bearings to minimize the effects.sodiumgood wrote:Has anyone been able to get their maglev to levitate without touching the side rails AT ALL? I have exhausted a great deal of effort to solve this problem and I have made very little progress towards a perfectly levitated train.
Mounds View Science Olympiad Alumnus, 2011-2014
MIT Science Olympiad Volunteer
MIT Science Olympiad Volunteer
-
- Member
- Posts: 3
- Joined: Mon May 06, 2013 7:24 pm
- Division: C
- State: TX
- Has thanked: 0
- Been thanked: 0
Re: MagLev C
Are magnet strips ideal for this year's parameter? I tried to place a 1+ kg cart on the track I bought last year from Science Kit, and it's touching the bottom magnet strips already. I am planning on replacing the strips with bar magnets with holes (5 lb max pull). Do you think this will be enough for a 2 kg car?
~JR
-
- Admin Emeritus
- Posts: 1115
- Joined: Tue May 10, 2011 8:25 pm
- Division: Grad
- State: TX
- Has thanked: 0
- Been thanked: 1 time
Re: MagLev C
We're having the same issue with pitsco magnet strips. One suggestion is to try doubling up on the magnets on your car, but I haven't tried it yet. I know some people were able to levitate more than 2kg without rare earth magnets last year so there must be a way.
'If you're the smartest person in the room, you're in the wrong room' - Unknown
-
- Member
- Posts: 96
- Joined: Tue Dec 27, 2011 12:32 pm
- Division: Grad
- State: MN
- Has thanked: 0
- Been thanked: 0
Re: MagLev C
In my experience, those magnet strips won't cut it for anything over a kilogram. Doubling up could work, but I'd recommend moving to ceramic block magnets, and by doing some searching it can actually be pretty affordable.iwonder wrote:We're having the same issue with pitsco magnet strips. One suggestion is to try doubling up on the magnets on your car, but I haven't tried it yet. I know some people were able to levitate more than 2kg without rare earth magnets last year so there must be a way.
Mounds View Science Olympiad Alumnus, 2011-2014
MIT Science Olympiad Volunteer
MIT Science Olympiad Volunteer