If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#651
|
|||
|
|||
Thrown out of an FBO...
On Sat, 18 Nov 2006 08:18:50 -0700, Chris M wrote in
: This conversation is no longer aviation related, so please take it to another forum ... I'm happy to do that, just as soon as you are able to direct all the other off topic posts to their appropriate newsgroups. :-) |
#652
|
|||
|
|||
PHIL Thrown out of an FBO...
It was obvious that heavier
things fall faster (feather, stone, duh) Actually, they don't. Correct. But it was obvious that they do. Jose -- "Never trust anything that can think for itself, if you can't see where it keeps its brain." (chapter 10 of book 3 - Harry Potter). for Email, make the obvious change in the address. |
#653
|
|||
|
|||
PHIL Thrown out of an FBO...
Jose,
But it was obvious that they do. Uhm, no. And Newton's law never said anything remotely like that. -- Thomas Borchert (EDDH) |
#654
|
|||
|
|||
PHIL Thrown out of an FBO...
On Sat, 18 Nov 2006 14:47:52 +0100, Thomas Borchert
wrote: Jose, It was obvious that heavier things fall faster (feather, stone, duh) Drop a sheet of paper (airfoil) and a peanut that weighs the same off a tall building. Which will get to the ground/pavement sooner (no wind) Actually, they don't. Roger Halstead (K8RI & ARRL life member) (N833R, S# CD-2 Worlds oldest Debonair) www.rogerhalstead.com |
#655
|
|||
|
|||
PHIL Thrown out of an FBO...
On Sat, 18 Nov 2006 23:16:30 +0100, Thomas Borchert
wrote: Jose, But it was obvious that they do. Uhm, no. And Newton's law never said anything remotely like that. Thomas. consider what Jose is actually saying. If it had been OBVIOUS that everything fell at the SAME rate, Galileo could saved himself the trouble of climbing all those stairs. Since GG did go to all that trouble, at least SOME people must have held an idea that needed disproving. Don |
#656
|
|||
|
|||
PHIL Thrown out of an FBO...
Jose wrote:
It was obvious that heavier things fall faster (feather, stone, duh) Actually, they don't. Correct. But it was obvious that they do. Boy, I hate to be pedantic about this, but in a vacuum the heavier object _will_ reach the surface of the earth faster than a lighter one if both are released the same height above the ground. First, the forces are equal on a mass Mo and the earth Me a distance h apart from their gravitational centers; the equation being: F = G*Mo*Me/(h*h) The acceleration of the earth (Ae) and object (Ao) relative to a fixed frame of reference are derived from F = m*a and the above gravitational equation: Ae = G*Mo/(h*h) Ao = G*Me/(h*h) The net closing acceleration in a fixed frame is: A = Ae + Ao Therefo A = G*(Me + Mo)/(h*h) But since Me Mo (Me ~= 5.98*10^24 kg), then to a very good approximation we can ignore adding Mo up to values of ~10^18 kg and say the closing acceleration is just: A ~= G*Me/(h*h) But the bottom line is under "ideal" conditions a heavy stone "falls" a teeny tiny miniscule bit faster to the earth than a light feather would. End of pedantry. ;-) (G ~= 6.67*10^-11 N*m^2/kg^2 and h ~= 6.37*10^6 m) |
#657
|
|||
|
|||
PHIL Thrown out of an FBO...
Thomas Borchert wrote in
: Crash, PROBABILITY, not POSSIBILITY. Big difference. I know. I mistyped. Still: Nothing happens if it has zero probability of happening. Actually, that is not true unless the set of outcomes is discrete and finite. To see this, consider the real interval U = [0, 1]. Denote by R the subset of rational numbers in U. The set of irrational numbers, Q = U/R is dense in U, therefore, the probability of picking an rational number in U at random is zero. Yet, it is not impossible. In addition, with a continuous probability density function, the probability of picking any given element is zero, yet some specific element is picked etc etc. Zero probability does not mean impossibility. http://www.cs.cmu.edu/~ndr/ProbabilityParadox.html http://en.wikipedia.org/wiki/Almost_surely Sinan -- A. Sinan Unur (remove .invalid and reverse each component for email address) |
#658
|
|||
|
|||
PHIL Thrown out of an FBO...
In article ,
Jim Logajan wrote: Boy, I hate to be pedantic about this, but in a vacuum the heavier object _will_ reach the surface of the earth faster than a lighter one if both are released the same height above the ground. That I'll buy. (unless they are dropped at the same time) [snip] But the bottom line is under "ideal" conditions a heavy stone "falls" a teeny tiny miniscule bit faster to the earth than a light feather would. um, not quite. The force on the more massive object is still just proportional to the earth's mass. What happens is the earth moves towards the more massive object more so than towards the less massive object. Or have I totally botched my freshman physics? -- Bob Noel Looking for a sig the lawyers will hate |
#659
|
|||
|
|||
PHIL Thrown out of an FBO...
Yes.
mike "Thomas Borchert" wrote in message ... Mike, As demonstrated on one of the lunar landings when (I forget which) the astronaut dropped a feather and a hammer and they fell together. Maybe, if one believes strongly enough in it, they WILL fall at different speeds. Can you disprove that? ;-) -- Thomas Borchert (EDDH) |
#660
|
|||
|
|||
PHIL Thrown out of an FBO...
All he's saying is that to the people of the time, things obviously fell at
different speeds. They weren't aware of air resistance being a factor. mike "Thomas Borchert" wrote in message ... Jose, But it was obvious that they do. Uhm, no. And Newton's law never said anything remotely like that. -- Thomas Borchert (EDDH) |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
I think old planes should be thrown away !!! | Tristan Beeline | Restoration | 6 | January 20th 06 04:05 AM |
Rocks Thrown at Border Patrol Chopper | [email protected] | Piloting | 101 | September 1st 05 12:10 PM |