197 reputation
214
bio website math.stackexchange.com/users/…
location Champaign, IL
age 35
visits member for 3 years, 2 months
seen Apr 13 at 22:15

Amateur mathematician, professional software engineer. Interested in all kinds of math, becoming a better mathematician, and helping others do the same.

email: jdb1729 (at) gmail.com

let's be friends: http://facebook.com/jdb1729


Mar
25
revised Iodine-131 half-life and reality
explain risk
Mar
24
comment Iodine-131 half-life and reality
Yes, but Xenon has no biological role and I don't know in what amounts it is ordinarily present in e.g. the thyroid or bone. The point is that the tiny amounts produced by the decay of Iodine 131 would be harmless. If the amounts of Xenon were large enough to be harmful, a person would already be dead from the radiation. For what it's worth, I found this page home.earthlink.net/~sweetwind7/thyca/thyca.html with a similar explanation. It claims that the same would be true even in a fantasy universe where Iodine 131 decays to Arsenic.
Mar
24
revised Iodine-131 half-life and reality
simplify
Mar
24
revised Iodine-131 half-life and reality
typo
Mar
24
revised Iodine-131 half-life and reality
explain risk; deleted 2 characters in body
Mar
24
answered Iodine-131 half-life and reality
Mar
23
awarded  Benefactor
Mar
23
revised Do Alkaline batteries, NiMH, rechargeable alkaline, Lithium AA, all have similar MAX POWER?
link internal resistance, correct spelling, remove unnecessary mathcode
Mar
23
revised Do Alkaline batteries, NiMH, rechargeable alkaline, Lithium AA, all have similar MAX POWER?
fix name
Mar
23
revised Do Alkaline batteries, NiMH, rechargeable alkaline, Lithium AA, all have similar MAX POWER?
conclude better
Mar
23
revised Do Alkaline batteries, NiMH, rechargeable alkaline, Lithium AA, all have similar MAX POWER?
wiimote
Mar
22
revised Can a car get better mileage driving over hills?
fix punctuation
Mar
22
comment Can a car get better mileage driving over hills?
Lawrence, the flat road must be curved because it has the same length as the hilly road and connects the same endpoints. Neither road is straight.
Mar
22
revised Do Alkaline batteries, NiMH, rechargeable alkaline, Lithium AA, all have similar MAX POWER?
pretty math
Mar
22
awarded  Teacher
Mar
22
answered Do Alkaline batteries, NiMH, rechargeable alkaline, Lithium AA, all have similar MAX POWER?
Mar
22
comment Can a car get better mileage driving over hills?
The flat road must be curved, not straight, because it has the same endpoints as the hilly road and both are the same length.
Mar
22
accepted Double-slit experiment with alternating on-off switch
Mar
22
comment Can a car get better mileage driving over hills?
This is pretty convincing, thanks.
Mar
20
comment Can a car get better mileage driving over hills?
Do the uphill and downhill parts of the road have the same slope, or equivalently (because of the same-elevation constraint), do they have the same length? If not, what determines the ratio? Also, are you saying that the most efficient mileage on the flat road is obtained by driving at the slowest possible speed? (I see that this minimizes air resistance but I just want to confirm). Favorite answer so far but having some trouble working out a specific example.