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1answer
13 views

illuminance on a slope plane

I am trying to understand the illuminance from an extended source(sky dome) on an inclined plane. The article I am reading has beautifully explained it. Yet I don't understand the angles and boundary ...
-2
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1answer
54 views

What state of matter is thunder? [on hold]

I know of solid, liquid and gaseous states of matter but what state of matter is thunder? Is it gas, liquid or solid?
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0answers
56 views

How to Calculate the Distance from Lightning? [closed]

It is a dark and stormy night, when suddenly you see a flash of light. Three and a half second later you hear the thunder. Given that the speed of sound in air is about 340 m/s, how far away was the ...
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1answer
33 views

Is illuminance defined only on a surface normal to the flux?

Assuming on the below image the source is a point source, I can understand that since the light flux falls on dA is the same within the solid angle and since the intensity I = Φ/dω and E = Φ/dA it can ...
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2answers
34 views

Electric charge difference weapon? [closed]

We all know how lightning works: The clouds have a strong static charge and release that charge towards the ground. But could it be used as a weapon? Would a weapon of the following description work? ...
3
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0answers
37 views

Lightning sprites

Lightning usually occurs due to an electrostatic discharge between an electrically-charged cloud and the Earth's surface, or between clouds. There are also sprites, electrical discharges that occur ...
0
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1answer
65 views

Why lightning most likely occure in night?

This is a question based on my experience. I am not going to prove that lightning (succeed by thunder) never occure in day, but it seems it most likely occure in night. May the humidity of air become ...
0
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1answer
58 views

Laser-induced electrical discharge

Attracting lightning with an ion beam has been done in a lab but how strong of a laser is needed to reach the clouds to redirect the lightning bolt?
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2answers
59 views

Attracting lightning with an ion beam

Can an ion beam be strong enough to create a path for lightning to travel to the ion machine? This is what I found in a lab that may help: An ionization factor jτi (the product of electron beam ...
0
votes
1answer
44 views

Atoms Inside a Lightning Bolt

What happens to atoms trapped in lightning? Why do electrons not split an atom but can change them inside the bolt? Can atoms travel on a bolt?
0
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1answer
23 views

Explanation to the flow of charge

I came across a really cool Cymatics video: There is one part in the video which is unclear to me. Please refer to the snapshot below taken at 05:15. I see the equipment being close to a Van de ...
5
votes
1answer
84 views

Does a Tesla coil work in space?

If I took a Tesla coil into space, and then turned it on near, but not touching metal objects- would charge jump to the metal objects? It's my understanding I wouldn't see a flash, since the lightning ...
2
votes
2answers
96 views

Is wearing metal armor during lightning safe?

I recently saw in a television show that wearing a metal armor during lightning is good because metal provides the path of least resistance for electricity to flow to the ground. Now my question is,is ...
1
vote
1answer
222 views

What will be effects of harnessing lightning?

In Feynman's Lectures, volume 2, chapter 9, there is a mention of earth getting charged by thunderstorm lightning. It is the thunderstorms throughout the world that are charging the earth with an ...
0
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0answers
21 views

lightning and LTE modem

I have heard that lightning likes to hit to a person who is talking to the cell phone. Is it the same for LTE(4g) modem which is used only for the internet. I mean will my home be more attractive ...
2
votes
0answers
101 views

How does lightning flip a car?

http://www.standard.co.uk/news/london/car-flips-into-air-after-being-struck-by-lightning-in-freak-electrical-storm-accident-10366208.html and a few others ...
0
votes
1answer
42 views

How are charges formed in clouds during lightning?

How are charges formed in clouds that are responsible for lightning?
1
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1answer
128 views

Can lightning actually weld fillings in your teeth?

So, I remember sometime in my childhood, someone was teaching me about lightning safety, and they explained that it was important to crouch low but keep as little contact with the ground as possible, ...
1
vote
1answer
127 views

Is it dangerous to use the water tap/bathe/shower during a thunderstorm?

As the title says, is there any danger in touching the water tap or sitting in a bath tub etc. inside the house during a thunderstorm? I heard that it is dangerous, as the lightning could hit some ...
0
votes
2answers
181 views

What will happen when lightning strikes on the surface of the deep sea?

The lightning is having enormous amount of energy, as it strikes the ground it makes various electrical and magnetic effects. If the lightning strikes a tree, that will be burst by lightning. ...
13
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3answers
261 views

Why does lightning generate multiple branches?

Everyone have seen and knows how lightning occurs. But then I realized that lightning never occurs in straight lines but it follows branching. But Why is that so? Why can't lightning goes in straight ...
11
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3answers
2k views

Why do lightning rods have a sharp point at the top?

We know that a lightning rod or lightning conductor is a metal rod or metallic object mounted on top of an elevated structure and, if we look closely, most of them have a sharp point at the top. What ...
2
votes
1answer
360 views

Lightning Conductor Working

During a thunderstorm charges collect on clouds until a field which is more than the air's dielectric strength is created. Because now there is a potential difference between the ground (0 Volts) and ...
2
votes
1answer
90 views

Why do nuclear bomb explosions create an array of visible electric discharges in the form of lightening in the upper atmosphere?

I've seen videos on the internet, showing nuclear bomb test explosions, and there appears to be a large amount of visible lightening discharging numerous times over the development of the mushroom ...
0
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0answers
79 views

Does lightning have a thickness?

We have calculated (probably measured) the speed, temperature and voltage of lightning so does lightning have a thickness? Note: When a lightning occur it heats up the air rapidly causing the air to ...
0
votes
0answers
120 views

Does a lightning strike have a physical weight?

A lot seems to be unknown about lightning and it is possibly a source of dark energy at the instance of the strike. So if we were to place say a 10kg lightning rod (earthed) on a set of insulated ...
6
votes
3answers
221 views

What would it take to cause lightning to jump between the Moon and the Earth?

This question comes from @Floris' speculation at the end of his excellent answer about what it would take to kill everyone on the Earth with electricity. Doing all this in 1/10th of a second ...
0
votes
2answers
147 views

Is lightning an example of energy emision from accelerated charge?

I have always heard that the inconsistency in explaining atomic models with classical mechanics was that the study of electrical charges had shown that whenever a charge is accelerated, it emits light ...
21
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4answers
7k views

If air cannot conduct electricity, how can lightning happen?

If air cannot conduct electricity, how can lightning happen?
1
vote
2answers
398 views

Is it possible to calculate the energy of a spark?

I am not a physicist, but this question came to me and I need to answer it, and I think that you guys can help me. Is it possible to calculate the energy in a spark? For example in a lighter with ...
0
votes
4answers
149 views

On what basis is it said that lightning does not strike the same place twice?

Why is it that atmospheric lightning cannot strike twice in the same place? I have heard this several times before, and recently I watched the movie "War of The Worlds", where the character played by ...
3
votes
2answers
59 views

Antenna to characterise lightning

what is the power spectrum and frequency spectrum of lightning. Can we calculate the Wattage in a lightning storm, can we draw useful power from it. I would like to build an antenna and receiver to ...
0
votes
1answer
120 views

Ball lightning: How are they formed?

Ball lightning: How are they formed? According to some Chinese researchers: These strange balls of electricity are seen during intense thunderstorms as glowing orbs. They can be yellow, white, ...
5
votes
1answer
395 views

Why some thunders sound deeper while others sound snappier?

Why does some thunder sound deeper and lower in pitch while others sound snappier and higher in pitch? I don't think there should be any difference between the lightnings and so the thunders sound be ...
2
votes
1answer
49 views

How can similar lightning strikes produce thunder with different time durations?

Here in Florida, lightning happens quite often. On occasion, I have noticed that one bolt will discharge and its resultant boom will be very very short, and then a second later another bolt will ...
14
votes
3answers
2k views

Why is the shape of lightning or an electric spark a zig-zag line?

Why is the shape of the lightning (or an electric spark) always of a zig-zag nature? Why is it never just a straight line? Image source.
1
vote
1answer
39 views

Can ligthning produce a reverbed sound if it falls on a high-tension line?

Last night, a rather strange noise woke me up around 5 am. It was like if a normal thunder sound had been fed to a reverb/delay box. As I was getting back to sleep afterwards, I could hear the sound ...
1
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2answers
419 views

Why is Lightning referred to as High frequency source?

Lightning strike is categorized as DC because of its electrostatic nature. The negative flash/stroke is found to have 200KA of current with a voltage close to 300KV (cloud to ground). But why is it ...
22
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1answer
2k views

Is it possible to overload a lightning rod?

A couple of weeks ago we had a big storm roll through the Chicago area. I watched as the city's skyscrapers were struck multiple times by lightning throughout the night and told my coworker about it ...
2
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2answers
506 views

Fork and Sheet Lightning

I've noticed that during British lightning storms, I have only ever seen sheet lightning However, on holiday in other countries, I frequently see Forked Lightning Q) Is this just caused by ...
0
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1answer
53 views

Natural electricity in the atmosphere - lightning

If air is such a poor electrical conductor, how can lightning be produced that appears to travel through it?
2
votes
1answer
77 views

Protect drone from lightning [closed]

I am designing a dirigible, robotic drone. It is basically a polyurethane airship, approx 3.6 m length and 2.1 m diameter. I am worried about lightnings: as far as I know, a Faraday Cage should be ...
1
vote
1answer
444 views

Why does lightning cause sound?

If I understand correctly, lightning is the discharge of electricity from the atmosphere into the planet. However, if I switch on a lamp, the wires are not causing thunder (or any audible sound). ...
5
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1answer
2k views

Do high voltage power lines attract lightning strikes?

I always thought that high voltage power lines would attract a lightning strike more than other structures in the same area. Turns out I was wrong. My neighbor's chimney got struck by lightning and it ...
1
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2answers
456 views

How does a lightning striking stall a moving car?

I am currently an undergraduate student leading a discussion section for an introductory electricity and magnetism course. I was asked this question that I was unable to answer and I am hoping for ...
2
votes
1answer
607 views

Lightning on my Car

Could anyone clarify to me the following: Lightning gives off high current when it hits a car/vehicle, and since the electrical components of the car is grounded on the chassis, are there ...
3
votes
1answer
141 views

Electricity from lightning

According to the internet, a lightning strike contains about 5 billion joules or 5 GJ. How was this calculated? Another thing: Once the lightning strike a metal grounded rod, a current will flow. ...
39
votes
6answers
8k views

Without seeing the lightning, can you tell how far away it struck by how the thunder sounds?

Is there any way to tell how far away a lightning strike is by how its thunder sounds? I thought one way might be by using the fact that higher frequencies travel faster than lower frequencies. Would ...
2
votes
0answers
53 views

Layman explanation and demonstration of positive lightning

Inspired by the thunderstorm overhead, and after reading the question and answers Voltage and current of positive lightning - what is an effective means to explain this phenomenon to a layman? Also, ...
2
votes
1answer
175 views

Why does cloud-ground lightning occur so much less frequently over ocean?

I was talking with an acquaintance about lightning, and we came up with opposite theories and predictions for the frequency of lightning over ocean. My theory is that since seawater is a fluid ...