7,200 reputation
1625
bio website en.wikipedia.org/wiki/…
location United States
age 70
visits member for 3 years
seen 11 hours ago

BS Mechanical Engr.
PhD CS(AI)
CS Prof (4yr)
Numerous consulting jobs.
15 yr at http://www.pharsight.com
Published book on CS & several articles
4 kids, 2 grand
Pilot(student)

P.S. The picture is a Beta-prime distribution. It shows the program speedup factors you can get if you see a problem twice in 2, 3, 4, and 5 samples.


11h
comment What is a Physically Accurate Explanation for the Kutta Condition?
I'm struggling to follow this, but I'm very impressed (which doesn't mean much).
1d
comment Is voltage always proportional to its derivative?
You're dropping off the C (capacitance) and R (resistance) parts. Everything depends on those.
2d
comment Do all elements spectrum lines fall within the visible light range?
There are ultraviolet and infrared lasers.
Sep
13
comment Is airplane moving slower when air is less dense?
Airplanes automatically adjust their speed so as to get sufficient lift, so at higher altitude they go faster. Propeller-driven planes capable of high-altitude flight automatically adjust propeller pitch to maintain chosen RPM. Engines lose power due to less oxygen, except they compensate with turbochargers. The pilot controls power (manifold pressure setting), propeller pitch (RPM setting), and indicated air speed (elevator trim). At a given indicated air speed, true air speed is higher at higher altitude.
Sep
13
comment Does the sun “drag the solar system through space”?
The video has very pretty graphics, however it doesn't really say anything. It says heliocentric motion and helical motion are different, but the difference is in perception only.
Sep
12
revised U.S. Standard Atmosphere
added 432 characters in body
Sep
12
revised U.S. Standard Atmosphere
added 74 characters in body
Sep
12
answered U.S. Standard Atmosphere
Sep
12
comment What happens to a photon after it is absorbed by an antenna?
Receiving antennas work because the electromagnetic wave excites EMF in the a antenna wire. It makes the electrons (or charge carriers) in the wire feel force and move. In so doing, energy is removed from the wave. When a photon of light boosts an electron from one orbit to the next, it is the same thing, but on a quantum level.
Sep
11
awarded  Yearling
Sep
10
answered Why does the Metropolis algorithm allow changes even for ∆E > 0?
Sep
10
comment What are washers for?
@jnovacho: I'm under the impression that the cut in a split washer does two things: 1) apply spring pressure (so the bolt remains under tension so it won't loosen further even if it loosens a bit, and 2) to cut into the bolt head if it tries to rotate counter-clockwise. Note it is shaped to allow clockwise motion, but it resists counter-clockwise by digging in. (They are called "lock washers".)
Sep
9
answered Number of blades in a fan
Sep
8
comment A problem says : a car starts from rest and undergoes a constant acceleration. It travels 5 m in the…?
@Maher: Yes, its average speed was 5m/s, but it did not travel the whole distance at that speed. At the start of the second, its speed was zero, right? At the end of the second, its speed has to be larger than 5m/s, right? because it it was 0 at the start, and 5 at the end, its average would have to be less than 5, right? The average is 5, but the speed changes from 0 at the start to something more than 5 at the end, 10 in fact. Keep in mind that acceleration is the amount that speed changes every second. That's why it is meters per second per second.
Sep
8
answered A problem says : a car starts from rest and undergoes a constant acceleration. It travels 5 m in the…?
Sep
7
awarded  Nice Answer
Sep
5
comment Ways of finding average accelleration
Average acceleration is total change in speed divided by the time in which it takes place. If the speed is 0 to start with, and 3 second later it is 2.1 then, yes, the average acceleration is 0.7. However, that is average acceleration. If the acceleration was 2.1 for one second, and it coasted for an additional two seconds, the average over the 3 seconds would still be 0.7.
Sep
5
answered How does a knife cut things at the atomic level?
Sep
4
comment Static,total and velocity pressure at a point
@Bryson: The density is given, along with the volume. The area of the shaft entrance is given, so the velocity can be determined. Isn't that enough to determine pressures?
Sep
2
comment Will I be able to push a small object in front of me in the outer space?
You and the ball together have a center of mass. If you push the ball away, you will also move away, at a speed that keeps the center of mass in the same place.