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Author Topic: How to break a lamp filament by non contact method  (Read 8713 times)

Offline nidal

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Please help me to break the filament of 2.5 Volt torch bulb when it is switched on and kept 6 inches apart


 

Offline David Cooper

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Re: How to break a lamp filament by non contact method
« Reply #1 on: 28/02/2015 18:43:44 »
Put it near a black hole and let gravity tear it to pieces.
 

Offline Bored chemist

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Re: How to break a lamp filament by non contact method
« Reply #2 on: 01/03/2015 11:05:16 »
A lot of science fiction seems to be very keen on using lasers for everything.
In this case a laser is probably as good a way as any.
 

Offline evan_au

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Re: How to break a lamp filament by non contact method
« Reply #3 on: 01/03/2015 11:30:25 »
Please clarify. It's not quite clear what is to kept 6 inches apart?

Run a 2.5 Volt torch bulb on 5V. It will fail immediately. Make sure that the power supply is at least 6 inches from the light globe.

Or you could mount the light globe on a 6 inch stick, and shake it vigorously while the light is turned on.

Or you could smash the light globe's glass envelope with a 6 inch stick - oxygen in the atmosphere will do the rest.

Note: the purpose of this site is not to do your homework for you!
 

Offline chiralSPO

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Re: How to break a lamp filament by non contact method
« Reply #4 on: 01/03/2015 13:25:14 »
A magnetic field should exert a force on the filament when the torch is on. If the magnet is strong enough, this could be enough to break it...
 

Offline nidal

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Re: How to break a lamp filament by non contact method
« Reply #5 on: 03/03/2015 14:27:57 »
The thing is that, a switched on torch bulb should blow off when it is kept closer to a "copper pot" kept 6 inches apart. I hope as per chiralSPO said a strong magnetic field will give the result. But the problem is how to magnetize a copper pot to that extend?, an alternating supply give to a copper pot may develop magnetic flux around it? Is it enough to break lamp filament? Or do I need to wind a copper coil inside that vessel to get that result?
 

Offline Colin2B

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Re: How to break a lamp filament by non contact method
« Reply #6 on: 03/03/2015 15:29:56 »
The thing is that, a switched on torch bulb should blow off when it is kept closer to a "copper pot" kept 6 inches apart. I hope as per chiralSPO said a strong magnetic field will give the result. But the problem is how to magnetize a copper pot to that extend?, an alternating supply give to a copper pot may develop magnetic flux around it? Is it enough to break lamp filament? Or do I need to wind a copper coil inside that vessel to get that result?

Can you clarify what you are trying to do?

Is this an illusion you are trying to create? If not, a copper pot will not blow a bulb unless it hits it. Putting a coil inside the pot won't help.

If you want to create an illusion, simplest method is as suggested, use over voltage. Start off at rated voltage and then switch to higher voltage when you want to blow the bulb.
 

Offline chiralSPO

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Re: How to break a lamp filament by non contact method
« Reply #7 on: 03/03/2015 16:28:30 »
Nidal, why are you so focused on a copper pot?
 

Offline nidal

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Re: How to break a lamp filament by non contact method
« Reply #8 on: 04/03/2015 13:46:13 »
Nidal, why are you so focused on a copper pot?

Any non magnetic material would do. Copper is preferred because of easiest availability.
 

Offline nidal

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Re: How to break a lamp filament by non contact method
« Reply #9 on: 04/03/2015 13:50:24 »
The thing is that, a switched on torch bulb should blow off when it is kept closer to a "copper pot" kept 6 inches apart. I hope as per chiralSPO said a strong magnetic field will give the result. But the problem is how to magnetize a copper pot to that extend?, an alternating supply give to a copper pot may develop magnetic flux around it? Is it enough to break lamp filament? Or do I need to wind a copper coil inside that vessel to get that result?

Can you clarify what you are trying to do?

Is this an illusion you are trying to create? If not, a copper pot will not blow a bulb unless it hits it. Putting a coil inside the pot won't help.

If you want to create an illusion, simplest method is as suggested, use over voltage. Start off at rated voltage and then switch to higher voltage when you want to blow the bulb.

Exactly Colin!!!! It is for an illusion. But the torch is not under our control !!!!
 

Offline Colin2B

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Re: How to break a lamp filament by non contact method
« Reply #10 on: 04/03/2015 16:30:43 »
Exactly Colin!!!! It is for an illusion. But the torch is not under our control !!!!

Full information is useful!
If the torch is provided by the 'mark' you might get a metal one which will stop any magnetic field reaching the filament. Even a plastic torch might have a metal reflector.
Laser won't work if it is a torch, problem with reflections and aiming.
Copper pot is irrelevant as it plays no part other than a prop. The strong electromagnet would need to be hidden under the table, but I can't see how you get around the shielding. In any case, the magnetic field would need to be very strong.
What if they turn up with an LED torch??

 

Offline wolfekeeper

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Re: How to break a lamp filament by non contact method
« Reply #11 on: 04/03/2015 17:58:04 »
Shoot it out with a pellet gun.
 

Offline evan_au

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Re: How to break a lamp filament by non contact method
« Reply #12 on: 04/03/2015 19:53:42 »
If they turn up with an LED torch, I expect you could do something more surprising, and make it glow yellow without it being switched on.

Economical "White" LED torches have a blue LED, with a yellow phosphor in front.

By turning on an invisible UV light, the phosphor should glow, just as it does when the blue LED is glowing (unless the lens absorbs UV strongly).

Don't wait too long. If/When the price of 3-color LEDs drops to be comparable to "White" LEDs - by combining a red, green and blue LED in the torch, it can produce different colors, and it requires no phosphor.

But beware: Short exposure to high-intensity UV will give you sunburn; long-term exposures could result in skin cancer and cataracts...   
« Last Edit: 04/03/2015 19:56:55 by evan_au »
 

Offline evan_au

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Re: How to break a lamp filament by non contact method
« Reply #13 on: 04/03/2015 20:15:34 »
Quote
But the problem is how to magnetize a copper pot to that extent? An alternating supply give to a copper pot may develop magnetic flux around it?

I am assuming that the target torch is a battery-powered torch with an incandescent globe, operating at 2.5V DC?

If you have an AC magnetic field powered by 50Hz or 60Hz mains, the conductive copper pot, and a potential magnesium-encased torch will have a current induced in them, partially cancelling the oscillating magnetic field (unless you first remove the lid of the pot). Also, the oscillating magnetic field will apply alternating forces to the filament before it can really stretch; these forces will almost cancel out due to the inertia of the lamp filament.

If however, you had a DC magnetic field from a permanent magnet, or an electromagnet fed from DC, the magnetic field would penetrate the copper pot, and mostly penetrate a magnesium torch case. The DC current, moving through a static magnetic field will produce a force on the light globe which lasts for a few seconds, and in a consistent direction. This may be enough to stress & break the lamp filament (but I don't know enough about the tensile strength of sintered tungsten above 1000C to comment).

Perhaps it is easier to use a strong permanent magnet for your scam, as it might be hard to hide the power cord for a DC electromagnet. Although any loose paper clips sticking to the pot may be a give-away...

PS: I hope you have a good supply of replacement 2.5V globes; now that LED torches are a comparable price, consume less power, can use smaller batteries making the torch lighter, and the LED torch is more rugged, it might become difficult for people to replace the globe in their torch after you break it.
 

Offline nidal

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Re: How to break a lamp filament by non contact method
« Reply #14 on: 10/03/2015 08:07:36 »
Let me tell you frank about the item we want to make.....

It is a duplicate rice puller. I don't know whether original rice puller really exist !!!!!

We want to make a "copper pot" which has a power to break a flash light with incandescent bulb of 2.5 Volt run by 2 dry cell batteries (This is a test done by the people who are going to buy this copper pot)

There are many tests for these kind of rice pullers. But all we need is to blow the flash light 6 inches away by non contact and must be kept inside the copper pot

See the link below:
newbielink:http://ricepuller.com/test/ [nonactive]

But I could not find any way to make such a thing with any scientific methods!!!! This is a big question for science.

I have got some RF discharge circuits, Electronic magnetic pulse generators, DC electro magnets, AC electromagnets etc. I don't know these things really works ???

If somebody could give me a right way of doing this will be very helpful.
 

Offline RD

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Re: How to break a lamp filament by non contact method
« Reply #15 on: 10/03/2015 11:05:22 »
Let me tell you frank about the item we want to make.....

It is a duplicate rice puller. I don't know whether original rice puller really exist !!!!!

Apparetly "rice pullers" are a magic-trick/scam ... http://rationalwiki.org/wiki/Rice_puller
« Last Edit: 10/03/2015 11:07:00 by RD »
 

Offline nidal

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Re: How to break a lamp filament by non contact method
« Reply #16 on: 10/03/2015 12:45:05 »
Yes Exactly... this is what we are looking at it.

We need a duplicate one !!!!! With only a incandescent flashlight test!!!

The people who are going to do the scam requires such one....
 

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Re: How to break a lamp filament by non contact method
« Reply #16 on: 10/03/2015 12:45:05 »

 

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