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Re: A once in a lifetime opportinity



brian whatcott wrote:
. . .
At 13:23 12/3/97 -0400, Ludwik wrote:
. . .
Radioactive
decay would be linear, rather than exponential, if the average decay
rate were to remain constant.

Actually, the prerequisite for exponential change is to have a constant
rate of growth or decay.

But how can the rate be kept constant
when the number of atoms (in the parent generation) becomes less and
less?

Does the bank rate of 10% p.a. change if it is your $84000 or my $44 ?

Sincerely,

Another semantic confounding! If N(t) is the number of yet
untransformed atoms "alive" at time t, then a constant (time) rate of
decay would be given by: dN(t)/dt = -k, where k is a constant.
Exponential decay is characterized by a constant "fractional" (time)
rate of decay: [dN(t)/dt]/N(t) = -k. That's why there is a definable
fractional (eg., half) life.

Hope this helps to avoid an endless semantic furor! (The bank rate is
conventionally specified as a fractional (%) rate.)
--


Bob Sciamanda sciamanda@edinboro.edu
Dept of Physics sciamanda@worldnet.att.net
Edinboro Univ of PA http://www.edinboro.edu/~sciamanda/home.html
Edinboro, PA (814)838-7185

Aristotle maintained that women have fewer teeth than men; although he
was twice married, it never occurred to him to verify this statement by
examining his wives' mouths.
The Impact of Science on Society, 1952.