Subject: Re:P-waves



Found what I was looking for ,,,,,  a animation of a P wave
http://www.geo.mtu.edu/UPSeis/images/P-wave_animation.gif

notice there is NO vertical motion, it is totally longitudinal
P waves travel like sound waves do  :)

=20
Hi Dave,
=20
    Oops ! P waves are of course longitudinal compression waves, BUT :-
=20
    Now  turn the animation at quite a sharp angle to the vertical to obser=
ve a =20
real P wave and you get quite a strong vertical component! If you observe a=
 local=20
quake directly under you, you will ONLY see a vertical component!=20
    Being body waves, P and S waves are usually refracted upwards as they n=
ear=20
the surface of the Earth, steepening the angle of approach. .

    Regards,

    Chris

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   Am I correct in assuming that your clocks use a vertical pendulum with a=
 period between 1 and 2 seconds?=20
Bryan Mumford

























=
Subject: Re:P-waves








Found what I was looking for ,,,,,  a animation of a P wave

http://www.geo.mtu.edu/UPSeis/images/P-wave_animation.gif


notice there is NO vertical motion, it is totally longitudinal

P waves travel like sound waves do  :)




 


Hi Dave,


 


    Oops ! P waves are of course longitudinal compressi=
on waves, BUT :-


 


    Now  turn the animation at quite a sharp angle=
 to the vertical to observe a  


real P wave and you get quite a strong vertical component! If you obse=
rve a local 


quake directly under you, you will ONLY see a vertical component! 


    Being body waves, P and S waves are usually refract=
ed upwards as they near 


the surface of the Earth, steepening the angle of approach. .



    Regards,=



 


    Chris


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 



   Am I correct =
in assuming that your clocks use a vertical pendulum with a period between =
1 and 2 seconds? 

Bryan Mumford