# someone explain to me why this wouldn't work.

Discussion in 'The Lounge' started by colbystephens, Feb 28, 2006.

1. ### colbystephens1 ton statusGMOTM Winner

Joined:
Feb 24, 2005
Posts:
10,924
20
Location:
Oregon
so in my physics class today we were discussing solonoids and toroids. if the solonoid or toroid is producing a magnetic (B) field inside its tubular structure, why could one not use it to move an object which responds to magnets? I asked my professor and he said that a B field cannot be used to accelerate an object, only to deflect its path. So I started wondering, why then if you put two magnets close together do they pull eachother into contact with one another? It makes sense in my head that if you were to put a small magnet in the B field produced inside one of these objects such that the north end of the small magnet faced the south end of the toroid/solonoid and the south end toward the north, the little magnet could be propelled through the solonoid/toroid. I suppose I have this fantasy of somehow finding a way to almost entirely neglect friction and make a transportation divice out of an enormous toroid which would act like a subway, and the wheels would act like alternators charging up huge capacitors which could run the toroid such that it would require little extra energy to be put into the system so it would almost be self-sufficient. we don't need to go into the physics of that, b/c it's just way too in depth. however, why can you not propel an object through a solonoid or indefinitely inside a toroid? Why can a B field not accelerate an object?

2. ### newyorkin1 ton status

Joined:
May 8, 2001
Posts:
16,555
157
Location:
I'm sure you could, but you'd have to have a computer control the electromagnets with an algorithm to figure out and control (or even just develope) the speed from inertia, which would always be different depending on the load of the train. I don't know if it's possible to control mechanically (I'm not a scientist, either). You would still need a battery or electric storage unit of some sort to start the train from a stop. The field produced inside a giant solenoid probably wouldn't be healthy to humans, though...

I think I'm jumbling ideas here, yours and others I've heard similar.

I think there are experiments with trains like that right now, but using electromagnets on the "track" and a fixed magnet under the train... Fully levitating, no contact with the rails = super smooth/quiet ride .

edit: just reread your idea, I see you accounted for the little extra external power needed, and I get your idea of the subway a little better...

3. ### Can CanPusher ManStaff MemberSuper Moderator

Joined:
Feb 17, 2000
Posts:
15,552
136
Location:
Oh man. Soloids, toroids, capacitors????

I'll stick to digging, thanks. I gotta go have a cigar and clear my head now......

4. ### colbystephens1 ton statusGMOTM Winner

Joined:
Feb 24, 2005
Posts:
10,924
20
Location:
Oregon
well, if it's not healthful for humans under those conditions, maybe we could transport other items that way, or, better yet, al-qaeda prisoners.

5. ### dogdaysunrise1/2 ton status

Joined:
Jan 19, 2005
Posts:
2,719
0
Location:
Winterpeg
holy crap. you guys are nerds... NERDS!

6. ### dogdaysunrise1/2 ton status

Joined:
Jan 19, 2005
Posts:
2,719
0
Location:
Winterpeg
you are going to make sooo much more in life then me

7. ### newyorkin1 ton status

Joined:
May 8, 2001
Posts:
16,555
157
Location:

That works...

I'm thinking, maybe the field wouldn't be that bad though. For commuters, it might just be like getting 2 MRI's a day...
Maybe it's the next wave of the conveyor belt...

8. ### colbystephens1 ton statusGMOTM Winner

Joined:
Feb 24, 2005
Posts:
10,924
20
Location:
Oregon

have you seen the goggles you're wearing in your avatar?

9. ### dogdaysunrise1/2 ton status

Joined:
Jan 19, 2005
Posts:
2,719
0
Location:
Winterpeg
hahahaha

thats not a picture of me. Its Bubbles from the Trailer Park Boys. I think only us Northerners know who they are.

10. ### colbystephens1 ton statusGMOTM Winner

Joined:
Feb 24, 2005
Posts:
10,924
20
Location:
Oregon
well, if it's not you, i think the fact that you watch something titled Trailer Park Boys and it has a character named "Bubbles" still proves my point. Whereaboots are you from then?

11. ### colbystephens1 ton statusGMOTM Winner

Joined:
Feb 24, 2005
Posts:
10,924
20
Location:
Oregon
that's kind of what i thought too. my professor said that in his graduate studies he had to get in an electromagnet and measure it's force. He didn't go into detail about that story - but kind of laughed it off as if it were a rather funny experience. I figured the conveyor belt thing might be as good as it gets - i figured the only way i could market it would be to say that there would be less maintinence b/c there would be considerably fewer moving parts to break and wear out. I had thought if one could make capsules which could go in this tube which would be coated with oil it would reduce friction, then you would only really have to maintain the hinges on the door to the toroid and perhaps the part which transfers electricity to the coils.

12. ### dogdaysunrise1/2 ton status

Joined:
Jan 19, 2005
Posts:
2,719
0
Location:
Winterpeg
the mighty city of Winnipeg. Found in the crotch of Canada known as Manitoba.

I HIGHLY recommend you find yourself an episode of Trailer Park Boys. Funniest show on t.v.

13. ### colbystephens1 ton statusGMOTM Winner

Joined:
Feb 24, 2005
Posts:
10,924
20
Location:
Oregon
so does that make you the beaver? man, you're lucky it doesn't get too hot there - can we say a little sweaty?

btw - i don't have a tv.

14. ### dogdaysunrise1/2 ton status

Joined:
Jan 19, 2005
Posts:
2,719
0
Location:
Winterpeg
unfortunitly it gets real hot here. and not a nice dry heat, but a ball stinkingly humid hot.

Its a fun city though alot of intresting stuff happens here.

15. ### Leper1/2 ton status

Joined:
Feb 18, 2005
Posts:
4,437
0
Location:
Dallas Baby!!!!
Is that where all the hookers are?

16. ### Leper1/2 ton status

Joined:
Feb 18, 2005
Posts:
4,437
0
Location:
Dallas Baby!!!!
On another note, I will soon be trying to break the first couple of laws of thermodynamics. I think that I have found a way to make a working perpetual motion machine. I am actually running into a problem in relation to your magnatism problem. I need to figure out the speed at which an electromagnet fully engages and if it engages north to south or south to north. And while it is engaging do the pole fields change in a linear direction?
Quick question for ya. Inside of a vacuum(not a cleaner)when heat that is generated, rises, how do you measure the rise? Does it have a physical property? And, does anyone happen to know where I can get a reasonably priced magnetic suspension bearing? I need to run one to overcome a problem I am going to have with friction loss.

17. ### HarryH31 ton statusAuthor

Joined:
May 31, 2000
Posts:
10,384
2
Location:
Georgetown, TX
18. ### Jagged1 ton status

Joined:
Apr 25, 2005
Posts:
11,460
1
Location:
SWVA

Remember the basic concept of heat? Atoms banging together at a faster rate?

In a vaccuum there would be no atoms, therefore no heat. Unless you're speaking of a solid/liquid in the vaccuum, then that object can have heat.

19. ### colbystephens1 ton statusGMOTM Winner

Joined:
Feb 24, 2005
Posts:
10,924
20
Location:
Oregon
it is true - you need something to heat. IIRC to measure it's heat rise you would multiply the number of moles by the change in temperature by the specific heat. This should give you a number in Joules or kJ, i don't remember. You will need a different specific heat for each phase change - i.e., if you have ice, you'll need the heat of reaction of fusion to get it melted, then the heat of reaction of vaporization to get it to a vapor. I'm pretty sure that's how it works. Didn't do real well in that chapter of chemistry - i gotta go back and review before my final in a couple weeks!

Joined:
Jan 24, 2003
Posts:
3,164