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Leo Bloom
04-24-2011, 08:02 PM

I stand in the rain in the open field. I sprinkle some salt on my tongue. I place the contact of the bulb, and wait. Then, zap.

Before my shriveled body shorts the circuit, is there any time, however brief, that the light would go on? I guess wattage, resistance, and voltage must be analyzed first...But can anyone suggest any outlines of a solution?

Bosda Di'Chi of Tricor
04-24-2011, 08:18 PM
If I had a lightbulb in my mouth and a lightning bolt hit me, would it incandesce?
No, but you would.

Colibri
04-24-2011, 08:32 PM
Given that the positive and negative terminals of the bulb would both be in electrical contact via the wet interior of your mouth, I don't see why current would pass through the filament and make it glow.

The Tao's Revenge
04-24-2011, 08:40 PM
http://www.nssl.noaa.gov/faq/faq_ltg.php/

How many volts and watts are in lightning?

Lightning can have 100 million to 1 billion volts, and contains billions of watts.

Is that number right at all? If so how do people survive lightening at all?

Anyway I was hoping to answer the op's question. OP your light bulb is at best probably 100 watts? It'll be over loaded and burn out like a camera flash, and probably explode in your mouth.

Der Trihs
04-24-2011, 08:57 PM
If so how do people survive lightening at all?IIRC, it's because skin is a fairly good insulator, and most of the energy tends to pass over the body instead of through it.

Leo Bloom
04-24-2011, 09:00 PM
Given that the positive and negative terminals of the bulb would both be in electrical contact via the wet interior of your mouth, I don't see why current would pass through the filament and make it glow.
Anyway to make me just an anode?

Civil Guy
04-24-2011, 09:03 PM
INA electrician, but I did sleep through, no, take physics class in college.

There maybe wouldn't be much voltage difference between the two terminals, so not much impetus for current - but heck, there could be hella voltage between the base of the bulb and the outside of the bulb, or other wierd, transient differentials - so there could be current through the filament - but maybe not the same way things normally work. We're not talking 'normal' here. So I think that it would be as TTR said, prolly all explode together (and let's not dwell on this), and yeah, a brief flash before all the lights went out, for good.

california jobcase
04-24-2011, 09:12 PM
Van DeGraff generators can jolt you with small (250,000 V, more or less) lightning bolts. Incandescent bulbs held in one's hand (or mouth) don't light up when the generator zaps you, but it's fun to light up a fluorescent tube that way.

Therefore, if you want to light up a bulb you're holding while getting struck by lightning, go fluorescent. Neon tubes should work, too.

johnpost
04-24-2011, 09:17 PM
just about everything is a conductor for lightning, it has just traveled miles through nonconductive air.

people live because not much of the energy of the bolt has gone through them. lightning bolts split many times as they approach the ground because there is much energy to dissipate.

trees get hit where the energy of the bolt goes into the tree and the trunk can explode.

RealityChuck
04-24-2011, 09:19 PM
You mean, like this? (http://blogs.westword.com/latestword/unclefester.jpg)

Leo Bloom
04-24-2011, 09:20 PM
Van DeGraff generators can jolt you with small (250,000 V, more or less) lightning bolts. Incandescent bulbs held in one's hand (or mouth) don't light up when the generator zaps you, but it's fun to light up a fluorescent tube that way.

Therefore, if you want to light up a bulb you're holding while getting struck by lightning, go fluorescent. Neon tubes should work, too.
Fantastic! (Civil Guy was informative, but not very civil.)
Can you put this in a little more detail so that I can tell it to people in cocktail parties? Length of x-watt bulb/human life proportions based on x parameters...?

WhyNot
04-24-2011, 09:23 PM
When people get hit by lightening, they often have internal burns along the path the lightening took to ground, even if you don't see damage on the outside. So anyone who is hit by lightening, even if they can walk away, should be taken to the ER. Sometimes, these burns are in very bad places, like the heart or kidneys, and they may survive the bolt, but die of their internal damage later. Sometimes, these burns are in not-so-bad places, like the connective tissue, and they may survive both the bolt and the burns.

Peremensoe
04-24-2011, 09:39 PM
You don't need lightning to make a fluorescent tube glow. Just hold it in the air under a high-voltage transmission line.

wbeaty
04-24-2011, 11:18 PM
Before my shriveled body shorts the circuit, is there any time, however brief, that the light would go on?

The argon inside the incandescent bulb would flash briefly like a strobelight.

Similar: put an incandescent bulb in your microwave oven. Argon plasma forms.

Leo Bloom
04-25-2011, 12:38 AM
I'd like to apologize to Civil. I read the beginning of his post incorrectly.

Machine Elf
04-25-2011, 07:18 AM
There maybe wouldn't be much voltage difference between the two terminals, so not much impetus for current...

This - maybe/probably. You need a significant voltage across the two terminals of the light bulb in order to drive an electrical current across the filament. Those terminals are maybe a 1/4-inch apart.

Lightning does produce voltage gradient in the earth wherever it strikes, often called step voltage; this is why it's possible (http://www.surgetek.co.za/more/step_and_touch_potentials.pdf) for lightning to kill you even if you aren't directly struck by it. In the same way as a voltage gradient is created in the earth, if you're struck in the head it's reasonable to expect a voltage gradient through your body, from head to toe. Is the gradient across your body strong enough to produce an adequate voltage differential in a 1/4" of distance to cause the filament to actually incandesce? Hard to say. Lightning is insanely powerful, but this may be asking a lot of it.

Napier
04-25-2011, 05:10 PM
You actually DON'T need a voltage between the terminals on an incandescent bulb to make the filament glow. You need current through the filament. You could weld the terminals together and make the filament glow, if you could cause a rapid enough change in the strength of the magnetic field where it passes through the loop formed by the filament and its supports.

This is actually a common mechanism by which lightning damages things. A bolt occurs someplace nearby, and a loop of conductor acts like a winding in a generator and passes current around. Or, a nearly-complete loop, such as two insulated wires that cross in a couple locations, develop enough voltage to blast through the insulation.

barbitu8
04-25-2011, 07:48 PM
just about everything is a conductor for lightning, it has just traveled miles through nonconductive air.

people live because not much of the energy of the bolt has gone through them. lightning bolts split many times as they approach the ground because there is much energy to dissipate.

trees get hit where the energy of the bolt goes into the tree and the trunk can explode.

This is entirely wrong. The air is ionized before a lightning bolt. Negative charges at the base of a cloud induce positive charges on the ground. Lightning bolts do not split as they approach the ground. Negative step lightning from the cloud will induce positive step lightning from the ground. Wikepedia: An initial bipolar discharge, or path of ionized air, starts from a negatively charged region of mixed water and ice in the thundercloud. Discharge ionized channels are known as leaders. The positive and negative charged leaders, generally a "stepped leader", proceed in opposite directions. The negatively-charged one proceeds downward in a number of quick jumps (steps). 90 percent of the leaders exceed 45 m (148 ft) in length, with most in the order of 50 to 100 m (164 to 492 feet).[26] As it continues to descend, the stepped leader may branch into a number of paths.[27] The progression of stepped leaders takes a comparatively long time (hundreds of milliseconds) to approach the ground. This initial phase involves a relatively small electric current (tens or hundreds of amperes), and the leader is almost invisible when compared with the subsequent lightning channel.

When a stepped leader approaches the ground, the presence of opposite charges on the ground enhances the strength of the electric field. The electric field is strongest on ground-connected objects whose tops are closest to the base of the thundercloud, such as trees and tall buildings. If the electric field is strong enough, a conductive discharge (called a positive streamer) can develop from these points. This was first theorized by Heinz Kasemir.[28][29] As the field increases, the positive streamer may evolve into a hotter, higher current leader which eventually connects to the descending stepped leader from the cloud. It is also possible for many streamers to develop from many different objects simultaneously, with only one connecting with the leader and forming the main discharge path. Photographs have been taken on which non-connected streamers are clearly visible.

Once a channel of ionized air is established between the cloud and ground this becomes a path of least resistance and allows for a much greater current to propagate from the Earth back up the leader into the cloud. This is the return stroke and it is the most luminous and noticeable part of the lightning discharge.

Leo Bloom
04-25-2011, 10:54 PM
You actually DON'T need a voltage between the terminals on an incandescent bulb to make the filament glow. You need current through the filament. You could weld the terminals together and make the filament glow, if you could cause a rapid enough change in the strength of the magnetic field where it passes through the loop formed by the filament and its supports.

This is actually a common mechanism by which lightning damages things. A bolt occurs someplace nearby, and a loop of conductor acts like a winding in a generator and passes current around. Or, a nearly-complete loop, such as two insulated wires that cross in a couple locations, develop enough voltage to blast through the insulation.

Where/how need/would I be acting, theoretically, as per OP?

Napier
04-26-2011, 05:21 PM
Where/how need/would I be acting, theoretically, as per OP?

I think the best thing to do - well, assuming you want to stay safe, the worst thing to do - would be to stand near or inside of some kind of conductor that preferably has a bit of a curl to it, like a partial loop, or even better an entire coil, that the lightning bolt is going to get conducted through. Then you will want to make sure that the plane of the filament and its supports is parallel to the plane of the loop or coil, so the two are most fully coupled. It's transformer windings you want to imitate, here. You also want to complete the circuit between the terminals. I guess if you have a gold front tooth, that might be best. Get fitted for a new grill, yo.

The Great Sun Jester
04-27-2011, 09:35 AM
It's lighning season here in Colorado. I'll see if I can't get out and do some field research on this one. But I think I need to do the coconut in the bonfire first...

Kyrie Eleison
04-27-2011, 10:37 AM
It's lighning season here in Colorado. I'll see if I can't get out and do some field research on this one. But I think I need to do the coconut in the bonfire first...
No reason you can't do them both at the same time. Here's how you start:

You put the light in the coconut...

04-27-2011, 11:33 AM
I'm going to state that the light glowing is possible but not probable. Given that lightning can posses not only high potential but also high current, a lightning strike could cause enough current and/or emf to transfer some current (same effect as Machine Elf mentioned for Step Voltage) to an incandescent light bulb that was in contact with your body and make it glow.

Since the described method doesn't necessarily create a certain path for the bolt's current it is likely that the bolt could hit you, do some major physical damage (hamburger) your body, and never send one milliamp through the bulb.

It's an ambiguous result mainly due to the close proximity of the light bulb's terminals to each other and the facts that your body probably won't /can't create a dedicated circuit for those terminals nor would the step voltage be high enough to send enough current through the filament.

Official Electric Type guy

DocCathode
04-27-2011, 06:30 PM
Anyway to make me just an anode?

Why would anybody want to be an [i]anode[/i[? :confused:

johnpost
04-27-2011, 06:59 PM
Anyway to make me just an anode?

Why would anybody want to be an [i]anode[/i[? :confused:

some are just givers and others not. i'm more a grid type myself, it's cooler.