What is Lightning: Definition and 262 Discussions

Lightning is a naturally occurring electrostatic discharge during which two electrically charged regions, both in the atmosphere or with one on the ground, temporarily equalize themselves, causing the instantaneous release of as much as one gigajoule of energy. This discharge may produce a wide range of electromagnetic radiation, from very hot plasma created by the rapid movement of electrons, to brilliant flashes of visible light in the form of black-body radiation. Lightning causes thunder, a sound from the shock wave which develops as gases in the vicinity of the discharge experience a sudden increase in pressure. Lightning occurs commonly during thunderstorms as well as other types of energetic weather systems, but volcanic lightning can also occur during volcanic eruptions.
The three main kinds of lightning are distinguished by where they occur: either inside a single thundercloud, between two different clouds, or between a cloud and the ground. Many other observational variants are recognized, including "heat lightning", which can be seen from a great distance but not heard; dry lightning, which can cause forest fires; and ball lightning, which is rarely observed scientifically.
Humans have deified lightning for millennia. Idiomatic expressions derived from lightning, such as the English expression "bolt from the blue", are common across languages.

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  1. V

    Solving a Lightning Storm Homework Problem

    Homework Statement A certain storm cloud has a potential of 1.50 x 10^8 V relative to a tree. If, during a lightning storm, 50.0 C of charge is transferred through this potential difference and 1.00% of the energy is absorbed by the tree, how much sap in the tree can be boiled away? Model...
  2. B

    Lightning Rod attached to railing of my balcony

    Hi @ all, I absolutely love thunderstorms & lightning and I'm used to go out on my balcony to watch them. Our (11-storey) house is equipped with a lightning rod, which, as I noticed today, is attached to the metal railing of my balcony (on the 5th floor). My question now is: What happens...
  3. J

    Can we create artificial lightning?

    Can we create artificial lightning ?
  4. D

    Probability of being struck by lightning

    Supposing I am a frequent mountain climber who encounters rains in 40% of the treks, what measures could I take to prevent myself being struck by lightening? Isn't the probality of my getting struck with the lightning just too high, assuming that most of the mountains "do not" have a...
  5. Ivan Seeking

    Oregon gets blasted by lightning

    This afternoon we had about as strong of a lightning storm as I've seen in the twenty years that we've been here. The weather was coming from the SE, which is somewhat unusual, and it may be that we saw what Eastern Oregon [the other side of the mountains] normally sees. I'm not sure what time...
  6. A

    Pacemakers and lightning bolts

    I'm working on a lightning bolt experiment at U of Washington to see how carbon composite materials hold up when hit by lightning. We have as much as a 40 kV 80 kA 50 us arc across a <1cm gap from a copper/tungsten electrode to a plate of carbon composite connected to ground. I know this must...
  7. thenewmans

    A rule for lightning that’s like the inverse square

    A point source of energy often follows the inverse square rule. So if I move my projector back twice as far, the image is 1/4 as bright. If I move half the distance closer to the TV, I can hear it 4 times louder. I’m guessing this rule doesn’t work so well for thunder and lightning since it’s...
  8. J

    What is the temperature of air during a corona discharge?

    ! Lightning ! How does lightning occur ? Please give a brief answer:smile: Thanks in advance :smile:
  9. DaTario

    Metalic apparatus to receive the discharge of a lightning near houses

    Hi All, I would like to know what is the main reason to build those metalic apparatus to receive the discharge of a lightning near houses. I am concerned with its shape and its physical explanation. Any help will be welcome, Thank you all Best wishes DaTario
  10. B

    Physics of Pointed vs. Rounded Lightning Rods

    What are the physics behind using a pointed lightning rod as opposed to a rounded one. I believe it has something to do with the electric field being concentrated to a point intensifying the field but can someone thoroughly explain it. Thanks!
  11. C

    Energy of a lightning bolt

    Homework Statement During a lightning strike, 30C of charge may move through a potential difference of 1.0 x 10^8 V in 0.02s. The total energy released by this lightning bolt is ______ J. Homework Equations I = q/t The Attempt at a Solution I'm really not sure what to do...
  12. M

    Lightning in Space: Fact or Fiction?

    does a phenomena such as lightning happen in the vacuum of space? it's often talks about in sci fi, but i wonder if it actually occurs (theoretically or actually) i tried a google search which turned up nothing.
  13. N

    Volcanic Lightning: Why is it Different?

    so why is there lightning in a volcanic eruption? why is the lightning a different color? maybe we could make these eruptions on purpose or similar scenarios to make lightning? thanks for you input!
  14. M

    So, Lightning Decides to Strikes a Sphere

    Homework Statement 1. Lightning strikes a dielectric sphere (Relative Permeability=1.2, Conductivity=10 S/m) of radius 0.1 m at time t=0, depositing uniformly in the sphere a total charge 1 mC. Determine for all t, the electric field intensity - E(Volts/m) & current density - J(Ampere/m^2)...
  15. Loren Booda

    Lightning as a measure of global warming

    1. Is an annual increase of lightning strikes worldwide a measure of global warming? 2. What has been the correlation between such discharges and temperature in recent decades?
  16. B

    Ball Lightning Debunk, New Proposal

    Ball lightning occurs after lightning strikes and also in the dry season in clear weather. It has been observed to pass through closed glass windows and to penetrate pressurized aluminum aircraft at altitude. (1.) There is no experimental evidence to examine because it has never been created...
  17. B

    Lightning Strike: Examining Electric Field, Capacitance & Power

    Homework Statement Lighting strike: Storm clouds build up large negative charges that dwell in a charge center. Suppose a storm cloud has -25 C in a charge center located 10 km above the ground. The negative charge center attracts an equal amount of positive charge that is spread on the...
  18. J

    Can Lightning Travel Through a Vacuum?

    Can lightning travel through vacuum? Does sitting in a vacuum chamber reduce/increase/no effect the probability of being hit by lightning? If lightning can travel through vacuum, I would imagine there wouldn't be any heat or light - hence it would be just an electric shock. True?
  19. J

    Can lightning be captured in different colors through photography techniques?

    Hello, i just found this photo http://www.ulozisko.sk/obrazky/128788/n1557987245_147143_160.jpg and I am wondering if this could be real somehow, or it had to be done via photoshop Thanks for reply
  20. S

    Franklin's lightning bells. Easy Question.

    Franklin's lightning bells. Easy Question. Please Help! Homework Statement Assume (for this part only) that the metal bell on the left was not grounded but connected to an insulator. Describe the changes as compared to question 4. So the franklin lighting bells experiment has a bell on the...
  21. K

    What happens to the current when lightning strikes a swimming pool?

    Hi all, In response to the above question, i read somewhere before that when lightning strikes a pool, or the sea, the current will dissipate along the water surface. The current will penetrate only to a small depth into the water. A simple search on Google throws up the simple...
  22. Loren Booda

    What is the maximum path that lightning can travel?

    Where does lightning have the potential to travel farther - vertically or horizontally?
  23. wolram

    Is There a New Theory for Ball Lightning?

    http://arxiv.org/PS_cache/arxiv/pdf/0811/0811.4640v1.pdf The maths is to much for me, but this paper seems to explain some of the characteristics of BL.
  24. R

    Can We Store Lightning Energy?

    Hey everybody, i want to know if its possible to "condensated"; or "store" the energy of a lighting Ray (The Ray of the Thunder)...cause i remember something about it that i saw once in the Discovery channel...i mean...is there any possibility to storage that energy so we could use it in perhaps...
  25. S

    Lightning Grounding: Why it Travels to Earth

    Hello, yes another GROUNDING question :) Can anyone tell me why lightning wants to travel to the Earth? and what happens to all that current that it carries after going into the Earth. Like what does the Earth do with it.. are there positive ions that neutralizes everything or what?
  26. C

    How did Sauropods protect themselves against lightning

    These huge animals must have been very vulnerable to being hit by lightning. Also, I think that in the Jurassic the climate was warmer and there were more thunderstorms.
  27. turbo

    Amazing slo-mo of lightning strike.

    This is really beautiful - especially all the branching and arcing that occurs before ground contact is made and the main discharge occurs.
  28. G

    Lightning connected with the magnetism of Earth core?

    Thunder in relation to Earth's core. Is there a relation to how the Earth's core revolves and circulates regarding thunder? What if one would track the amount of energy beeing surged and what direction it might seem to be heading, if has a direction? Is there a inderect link between lightning...
  29. T

    Lightning in Sky: Why Don't I Hear Anything?

    i am tuan anh, i am from vietnam very happy when join this forums i have one question when i see the lightning in the sky i don't hear nothing in it i don't understand why please help me thanks
  30. Ivan Seeking

    Surprising lightning observation

    Tonight I happened to check a "live" lightning map for activity, and noticed something odd. In about five separate areas of activity over the State of Oregon, separated by hundreds of miles and the Cascade mountains, the strike rate of all systems were changing, but ~equal, over a period of an...
  31. C

    Lightning Strike and electrical power surge

    Recently, lightning hit near my home (as best as I could tell, not my home directly) and caused considerable damage to my home computer. I have a wireless network with 2 desktops...one direct wired using ethernet cable and the other using a NIC card. When the lightning struck, my wired...
  32. T

    Relativistic Lightning on Train Problem

    Homework Statement Suppose the two lightning bolts shown in the figure 37.5a in the txtbook are simultaneous to an observer on the train. Show that they are not simultaneous to an observer on the ground. (Relevant Diagram Attached) Homework Equations The Attempt at a Solution...
  33. M

    Help evaluate the ball lightning energy

    Input data: window glass thickness: 3mm ball lightning diameter: 10cm discharge duration 30 seconds After the discharge there was 7cm round hole in the window glass (after freezing to atmosfere temperature). It was a real case in 1976 year in Frijazino city, near Moscow during school lesson.
  34. wolram

    Lightning Fast Internet Speed in a Remote Village

    I now have 8 Meg and it is nearly 7 according to download testers, amazing for a tiny village miles from anywhere.
  35. F

    Domain of ln(x): What numbers can be plugged in for ln(x) to make sense?

    I know this is a ridiculous question, but what is the domain of ln (x) ? Is it > 0 ? Thank you!
  36. W

    Lightning bolt electrons problem

    A strong lightning bolt transfers about 25 C to Earth. How many electrons are transferred? 1 electrons = 1.60E-19 so.. 25 / 1.60 E -19 = 1.5625E-18 electrons but the answer that my teacher gave us is 1.6 E 20 electrons what did i do wrong?
  37. S

    Is Earth Positively or Negatively Charged?

    i read from this site http://thunder.msfc.nasa.gov/primer/primer2.html that electrons from lower portion of clouds goes to ground beacuse of Earth's positive charge... but the below two sites tell that Earth is negatively charged... http://www.madsci.org/posts/archives...2284.Es.r.html...
  38. F

    Lightning question before the test : )

    How can I show that the sequence { 4^(n)/n! } converges to zero (by squeeze theorem)?? Thank you! : )
  39. F

    Lightning SERIES question

    can anyone explain why the summation from 0 to infinity of (-2)^(n)/3^(n+1) diverges? - Is it simply because the terms bounce between - and +?
  40. wolram

    Damage caused by ball lightning

    Does anyone have pictures or reference to damage caused by BL? The only major damage report i can find is in this Wiki article http://en.wikipedia.org/wiki/Ball_lightning Look under Esoteric. damage done to a peat bog, is there a better article on this? I would be most interested in...
  41. M

    Can lightning induce ozone formation in the upper atmosphere?

    I wonder if lightning in the upper atmosphere can create ozone? Anybody know what the chemical reaction would be?
  42. E

    Rotational Kinetic Energy -> Lightning Speed Running?

    Homework Statement Suppose a solid cylindrical flywheel has a mass of 200 kg and a radius of 0.8 m and rotates at a rate of 15,000 revolutions per minute. If you were able to convert all of its rotational kinetic energy into making you run, how fast would you be going? (Assume your mass is...
  43. D

    Why Does Lightning Zig-Zag Instead of Forming a Smooth Arc?

    Why doesn't the bolt make a smooth arc shape? Why doesn't it just follow a straight path to the ground?
  44. J

    What Happens to Electrons and Cloud Charges After Lightning Strikes?

    What happens to the electrons in the lightning after they hit the Earth soil? After these so many lightning hits the earth, won't there be excess of electrons in the earth? How do these electrons escape from the earth?
  45. C

    Does my lightning rod sound worrying to you?

    I have two lightning rods. One is at the highest point on my roof and has a pointed tip and is attached to a thick piece of copper that goes 8 feet into the ground. That one makes me feel safe. But the one attached to my solar array is horizontal in a 14 inch deep trench in the ground...
  46. F

    [3-in-1] Radioactivity detection, Lightning & Magnetic field strength

    1) Methods/equipment for radioactivity detection. For my high-school Chemistry studies, needs clarification. Geiger counter: A small chamber contains a high voltage electric field inside filled with inert gas. When ionizing particles/radiation enters the chamber, it will ionise the...
  47. V

    Is It Safer to Stay in Water or on Land During a Lightning Strike at the Beach?

    It is generally accepted that under lightning risk, it is not safe to be on open areas, and if in such a situation, better to lay on the ground to avoid being the higher feature. But what if you are on a beach. Is it safer to keep inside the water than laying on the sand? At the end, the...
  48. wolram

    LBH, Dark Matter & Ball Lightning: n-Dimensional Gravity

    http://www.citebase.org/abstract?id=oai%3AarXiv.org%3Aastro-ph%2F0104026 n-Dimensional Gravity: Little Black Holes, Dark Matter, and Ball Lightning Authors: Rabinowitz, Mario The gravitational field, and radiation from quantized gravitational atoms and little black holes (LBH) are...
  49. W

    Is Lightning Deflected to the West in the Western US due to Magnetic Fields?

    in a magnetic field the force is toward the center of the circular path, does this mean lightning deflects to the West ? in the western US at least.
  50. A

    Calculating Voltage of Cloud After Lightning Bolt Transfer

    Homework Statement The Electric field between a cloud and the ground is 1.0X10^6 N/C. If 35C of charge is transferred to the ground (lightning bolt) over a distance of 2.3km, what is the voltage of the cloud. Homework Equations q=mg/E? The Attempt at a Solution I don't have the...
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