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sundaraveena
11-24-2003, 10:55 PM
the air in the vicinity of a lightning is very hot, as high as 4-5 times that of the sun. the sudden heating causes air to expand and compress nearby air at rates faster than sound giving rise to a shock wave. this shock wave is heard as the loud thunder.

vasan
11-24-2003, 10:58 PM
the air in the vicinity of a lightning is very hot, as high as 4-5 times that of the sun. the sudden heating causes air to expand and compress nearby air at rates faster than sound giving rise to a shock wave. this shock wave is heard as the loud thunder.

Something wrong here... Shock waves are sound waves. You can't make it go faster than sound waves. Also, many times we see only lightening and not hear the thunder rolling.. why is that? I think the explanation is more complicated than that...

sundaraveena
11-24-2003, 11:04 PM
you are right, shock waves are sonic. the superheated air expands much faster and forms this shock wave.

sundaraveena
11-24-2003, 11:11 PM
as for second question,
thunder is a consequence of lightning and both are inevitable to occur together. sometimes it appears that we see a lightning but do not hear a thunder (this type of lightning without thunder is known as heat lightning ) . this happens because thunder being sound waves is attenuated within short distances (approx 10 miles) and depending on the geographical location sometimes you get to witness heat lightning.

gsatnan
11-24-2003, 11:19 PM
wow interesting stuff about thunder and lightning... it was really enlightning to get these informations about different things. Keep up the good work guys and post more interesting facts

sundaraveena
11-24-2003, 11:44 PM
if you see lightning 1 mile away, it will take approx 5 sec for thunder to reach you. next time you see a flash of lightning count the number of secs before the you hear thunder divide by five toget approx location of lightning.