The Naked Scientists

The Naked Scientists Forum

Author Topic: What makes lightning go "BOOM!"  (Read 6122 times)

Offline tony6789

  • Neilep Level Member
  • ******
  • Posts: 1127
    • View Profile
What makes lightning go "BOOM!"
« on: 27/03/2006 15:20:04 »
I understand that lightning is from negtivaly and positvely charged particles but what makes it go boom?

- Big T
« Last Edit: 08/04/2006 16:00:35 by ukmicky »


 

ROBERT

  • Guest
Re: What makes lightning go "BOOM!"
« Reply #1 on: 27/03/2006 17:26:16 »
" Lightning is a powerful natural electrostatic discharge produced during a thunderstorm. Lightning's abrupt electric discharge is accompanied by the emission of visible light and other forms of electromagnetic radiation. The electric current passing through the discharge channels rapidly heats and expands the air into plasma, producing acoustic shock waves (thunder) in the atmosphere."
http://en.wikipedia.org/wiki/Lightning

 

Offline Hadrian

  • Neilep Level Member
  • ******
  • Posts: 2175
  • Scallywag
    • View Profile
Re: What makes lightning go "BOOM!"
« Reply #2 on: 31/03/2006 18:41:23 »
I thought this might help

Lightning happens when a cloud builds up a separation of charge. The bottom of the cloud (facing the earth) has a negative charge (extra electrons) while the top of the cloud expels positive charges up and out into the upper atmosphere.  So the cloud has all this extra electrical energy on the side facing the earth, and eventually it dumps the energy down towards the earth, which tends to have a positive charge (for complex reasons) compared to the cloud's underbelly.  When the stroke begins, a series of little pulses of electricity come down from the cloud towards the earth at really high speeds (about 1/6 the speed of light!). These pulses are called steps, and the trail they pulse down along is called the step leader. (not ladder).  The air gets ionized along the step leader and so this column of air becomes a good conductor of electricity. So when the step leader (which is so faint that it is practically invisible) hits the earth, a "conducting wire" of air is set up from the cloud to the earth.  Now charge can flow, but the first charges to move are the ones at the bottom of the wire (near the earth).  So, the stroke (which is now visible) starts at the bottom (the earth) and runs UPWARDS from the ground! This return stroke produces the bright light and a lot of heat, which causes the air to expand suddenly, which causes a thunderclap.  


What you do speaks so loudly that I cannot hear what you say.
 

The Naked Scientists Forum

Re: What makes lightning go "BOOM!"
« Reply #2 on: 31/03/2006 18:41:23 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums