reply to post by Ghost375
1) You approximated "t" to be 2 hours. Why, exactly? What happens when you use the actual
length of the quake (6 minutes)?
2) The Earth was shifted on its axis by about 3.9 inches (10 cm), not 6 inches.
3) Both the initial and final velocities are 0. Did you halve the time, guess at what maximum velocity the shifting of the Earth's axis reached, and
use that to solve for its acceleration? If not, your answer for the measure of the shift's acceleration means nothing. If you did, you still had to
guess at the maximum velocity, which, again, leaves you with a completely inapplicable answer.
4) F = ma denotes the force "F" it takes to move an object of mass "m" at acceleration "a". This does not translate into the rotational force. What
you should be measuring is torque. If you do this, you will quickly notice that, to account for rotational acceleration in this way, you need a
tangential force. This sort of force is not provided by an earthquake - rather, the axial shift is due to a change in momentum (close, but, as they
say, no cigar), which causes a crustal displacement. The axis of rotation, itself, doesn't shift.
5) Gravity is a centripetal force, and, for a spherically symmetric body (which approximates the Earth), is perpendicular to the surface. The gravity
of an external mass cannot cause an axial shift unless there is some sort of significantly uneven distribution of mass. To suggest that gravity can
account for the shift is wrong.
Also, to equate rotational force (which, again, should be torque) with gravity is wrong. They are two completely different things.
A 1.5-Earth-mass object at Elenin's location does not account for an axial tilt. "How can an earthquake cause an earth shift that requires a force
greater than the mass of the earth itself?" It doesn't have to, because your "math" is contrived and full of holes and false assumptions. The
earthquake tilted the Earth by causing a shift in the Earth's mass. The force you calculated is wrong...earthquakes regularly and consistently have
enough energy to tilt the Earth, and to suggest that this one example is due to some nearby planet is irrational. And, even if a planet did exist
where Elenin is claimed to be, it would not be causing the Earth to shift on its axis - it would be tugging on us, not tilting us.
I love math. And I love physics. I hate seeing both mutilated like this.
edit on 19-3-2011 by CLPrime because: (no reason given)