Daily sea escape

Daily tides, daily sea escape and return, are the stretching of the Earth that are caused by another bodies, mainly the Moon and the Sun.

The gravitational force exerted by one body on another is not equal across the finite size of a body.


       tidal force

The gravitational force between two objects is  F = GMm/r^2

    G= gravitational constant
   M= mass of object-1
   m= mass of object-2
   r= distance between objects


the distance on the near side is (d -R),  on the far side is (d + R)

F1 = GMm/(d- R)^2 ,     F2 = GMm/(d+ R)^2

the force difference in these two forces is   DF = F2 - F1=  -4GMmR/d^3

The minus sign means F2 < F1, the force is less on the more distant side,
which force difference stretches the object and causes the tidal bulge.

stretch

A fixed point on the earth experiences the bulges as high tides twice a day by the rotation of the Earth. Tidal force effect on the Earth by the Moon is stronger than that of the Sun.


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 "The sea looked and fled;" (Psalm114:3)
 Israel exodus from Egypt was caused by a strong east wind (Exodus14:21), not tides.
 While the event was occurring, the sea would have escaped and returned as daily tidal cycle, because winds cannot change the rotation of the earth and the orbit of the sun and the moon.

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References
Solar System Astronomy, Lecture Number 12
Gravitational tides

Unrelated posts
 Psalms chapter 114

Psalms chapter 114

Hebrew-English transliteration and part of speech and interlinear translation of Tehillim 114


 

pronunciation  ~ ^ long vowel      a~   i^                       :e  :a  :o    very short vowel   ' Alef  glottal stop ` Ain   ? h. Het   strongly [h] t. Tet   strongly [t] s. Tsadi  sound like [ts] s  shin or samech ph   Pe [f]

part of speech pn    proper noun - 　status constructus m masculine f  feminine s  singular pl  plural pf  perfect impf  imperfect inf  infinitive part  participle conj  conjunction prep  preposition adv  adverb suf  suffix

1 b:es.~th  yisra~'el  mimms.ra~yim   be^th  ya`qobh  me~`am   ro`e~z
    prep-inf         pn          prep-pn　　　　msg-   pn m      prep-msg   msg part

  in-go-out     Israel     from-Egypt   house   Yacob    from-people  foreign


2 ha~y:etha~h  y:hu^ dha~h  l:eqa~d:esho^     yisra~'el   mamsh:elo^tha~w
   3sgf pf           pn               prep-msg-3sgmsuf      pn m     fpl-3sgmsuf

  she-became    Judah  to-his-sanctuary   Israel　  his- territories


3 hayya~m  ra~'a~h  wayya~no~s   hayyarde~n   yisso~bh   l:e'a~h.o^r
   m sg        3sg pf     prep-3sg impf    pn             3sgm impf  prep-adv

  the-sea   he-saw  and-he-fled   the-Jordan  he-turned   to- backward


4 heha~ri^m   ra~q:edhu^   k:e'e^li^m   g:ebha~`o^th  kibhne^   s.o~n
  prep-m pl      3pl pf            prep-m pl    f pl               prep-mpl-   f pl

  the-mountains   they-skipped   like-rams   the- hills  like-sons-of flock


5 mah  l:eka~     hayya~m   ki^  tha~nu^s  hayyarde~n  tisso~b  l:e'a~ho~r 
 pron-  prep-2sgm　 msg　　conj　2sgm impf    pn         2sgm impf   prep-adv

  what-to-you  the-sea   that   you-flee    the-Jordan  you-turn 　to-backward


6 heha~ri^m   tirq:edhu^  k:e'e^li^m   g:ebha~`o~th    kibhne^  s.o~n
   prep-mpl     2plm impf    prep- mpl      fpl                prep-mpl-   f pl

  the-mountains you-all-skipped  like-rams   hills   like-sons-of  flock


7 milliphne^   'a~dho^n  h.u^li^  'a~res.  milliphne^   ':elo^ah  ya`:aqo~b
 prep-prep-mpl-  msg       fsg imp    fsg     prep-prep-mpl-  msg-      pn m

  from-to-face-of   lord  writhe-you !  land   from-to-face-of  God-of Jacob


8 aho~phkhi^  has.s.u^r  ':aghm  ma~yim  h.lla~mi~sh  l:ema`:eno^  ma~yim
   msg part-      msg           msg-     m d       msg             prep-msg-     m d

  the-one-turning the-rock pool-of waters,  flint  to-fountain-of water



    notes ---------------------------------------------------------
 1 yisrael : people of Israel, descendants of Jacob
  yaqb : Jacob(another name Israel), a male leader

2 yehudah: territory of Judah

4 "kibhne^  s.o~n"
     LXX  "ως αρνία προβάτων" ("as lambs of sheep")

7 adon : load
  eloah, el : God
 "':elo^ah  ya`:aqo~b" ("God of Jacob"): one of names of God, a expression of the relation between individuals and God



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References
 Psalm114 text and voice   http://www.mechon-mamre.org/i/t/t26b4.htm
 interlinear bible     http://biblehub.com/interlinear/psalms/114.htm

Related post          psalm114 Japanese
Unrelated posts     Daily sea escape