Wednesday, January 6, 2010

F in Math, F in Physics, and B done with me please

Q-dipshit writes:

"If precedence is an issue, why are my answers correct?"

Precedence, particularly when typed sloppily the way you did, is but one issue that would have flubbed the math in your pseudo-physics. (Ask your college for a refund on your degrees.)

But more importantly, your answers are not correct, with multiple errors in both your math and physics compounding the incorrectness.

[1] Although you managed to correctly calculate the free-fall time (9.23 s) and what the velocity would have been at that time (90.4 m/s), re-using that same velocity to calculate a distance at a new time (14.74 s) with the equation d=vt is wrong, because it plugs in the velocity as if it were constant from 0 to 14.74, when it wasn't. (Physics: grade F)

[2] You managed to divide the distance you were calculating by 2 for no apparent reason, so even that distance (666.7 meters) is wrong. (Math: grade F)

[3] If you really wanted to know how far something would fall in 14.74 seconds, the proper equation to use:

    d = (1/2)a t^2
    d = (1/2)(9.8)(m/s^2) * (14.75 s)^2
    d = (1/2)(9.8)(14.75)^2 m
    d = (1/2)(9.8)(217.56) m
    d = 1066 m

[4] Coming up with a ratio of the distance it could have traveled in ~14 seconds to the distance it did travel (assuming the 3 errors above weren't in your work) might not have been bad.

  • Your wrong ratio was (666.7 m) / 417 m = 1.60
  • The ratio for a constant velocity should have been (1333.4 m)/(417 m) = 3.2, but this is also meaningless.
  • The ratio you sought was (1066 m)/(417 m) = 2.55

But no. You came up with a totally assinine & deft of meaning conclusion:

"Hence, if the South Tower fell at "free-fall speed" it would have fallen about [corrected: 2.55] times as far as it actually did fall in that time."

Your saying it should have fallen (1066 - 417=) 649 meters below street level.

[5] In addition to the above 4 gross errors in your math and physics, you can't seem to accept that a building collapse could happen in stages, some fast and some slow. You always want to lead us astray by starting the clock at some arbitrary point in time, stopping it at another, and saying everything that happened in the middle was uniform and consistent.

The above answers your question 1. Your question 2 isn't relevant either to the issue at hand or to your understanding. You can't even get calculation precedence correct much less notation; you refuse to provide an unambiguous notation (e.g., image of something from an equation editor like in Word). You wouldn't know what to do with my answer. You're just wasting my time so that your team in the Q group will have time to address your other errors.

Be a man of your word. Be done with me.

~TwentyTen