6,607 reputation
928
bio website embedinc.com/olin
location Littleton, Massachusetts
age 58
visits member for 1 year, 7 months
seen 20 hours ago

Electrical engineering consultant specializing in microcontrollers and the circuitry around them. Master of engineering in EE from Rensselaer Polytechnic Institute in 1980.

We are certified Microchip design partners, and have been in the top catagory consistantly since around 2000. Various free downloads related to developing PIC firmware and other things are available at http://www.embedinc.com/pic/dload.htm.


1d
comment Permanent magnet rail device
Their existance is proof they do work, so your question make no sense. Are you asking whether a particular video is fraudulent?
Sep
26
comment Existence of a physics-god
By bringing up god you already dragged this discussion into theology. This kind of nonsense simply doesn't belong here. -1 from me too.
Sep
25
comment What does it mean to have two phase coherent signals at different frequencies?
You can still talk about a phase relationship between two frequencies when they have a integer ratio, such as 3:2 in your example. In that case, you assume some reference, like the positive zero crossing, in each signal.
Sep
25
comment The earth is spinning, so why don't we jump and land on a different location?
@Holger: As the projectile falls back down, the discrepancy between its lateral speed and the ground's lateral speed decreases again, but the discrepancy still exists until the projectile hits the ground. The west offset distance is the time-integral of this lateral velocity discrepancy. The down portion of the flight contributes the same west offset as the up portion.
Sep
25
comment Sound Energy with respect to audio frequency
But you are asking about loudness, so you can't ignore whatever is preceiving the sound. Make up your mind what you are really asking about.
Sep
24
comment Sound Energy with respect to audio frequency
If you're asking about loudness, you'll have to take human (or whatever is preceiving the loudness) hearing into account. It would be better to deal with sound power first, then deal with loudness by defining a specific response curve.
Sep
24
comment Can there be a string so thin as to be invisible, but that can still support a visible weight?
@bobie: I don't see the point to your edit. Your version says the same thing the original did, just using words differently. The only difference is style, not content or correctness, so should be left up to the author unless it gets in the way of clarity (which the original didn't).
Sep
16
comment If the universe is expanding, what is it expanding into?
1: Into more universe. 2: Everywhere. 3: Nobody knows. 4: Nobody knows.
Sep
14
comment How to calculate when wheels are better than legs?
First, your "question" contains several assumptions that you haven't proven and I'm not at all sure are correct. This therefore can't be answered in its current form. Second, this is a biomechanics problem.
Sep
11
comment Is this scene from the A Team explainable by Physics?
@Aron: As I said in my answer, even if I was off by a order of magnitude, the result would still be the same. You link shows that muzzle velocity is almost 1800 m/s, but shell mass a bit lower than the 10 kg I used and the M1A1 tank a bit heavier than the 50 tons I used. All in all it seems I was low by a factor of 5. 0.8 miles/h speed change still isn't going to matter.
Sep
10
comment Is this scene from the A Team explainable by Physics?
Very little from The A Team is explainable by physics.
Sep
8
comment Where does the extra kinetic energy come from in a gravitational slingshot?
The energy comes from the kinetic energy of the planet going around the sun. The orbital speed of the planet is slowed down very slightly as the spacecraft passes by.
Sep
7
comment Formula for Electrical Arc Length
You look up the breakdown voltage of whatever material (like air) you want to arc thru. Then multiply that by the distance between electrodes and that's the voltage you need.
Sep
5
comment Why is it hard to make black clothes?
What material do you know that absorbes absolutely all visible light, reflecting nothing at all. "Nothing" is a rather small value. The same issue goes for white too. Some material would have to reflect all visible light.
Sep
5
comment What really happens atomically in an explosion?
The cigarette heats up a few oxygen and butane molecules, which causes them to combine, which releases heat, which heats up even more oxygen and butane molecules, etc, etc, boom.
Sep
4
comment How is voltage increased from a battery?
@Floris: My answer is "voltage wasn't increased", so of course I can't talk about how it was increased, since it wasn't.
Sep
4
comment How is voltage increased from a battery?
Whoever downvoted this: What exactly do you think is incorrect, misleading, or badly written? I have re-read what I wrote and still believe it to be correct.
Sep
4
comment How is voltage increased from a battery?
Yes, it is possible to convert from a few 10s of volts to 30 kV, but this makes absolutely no sense for a copter. The converter would take space, weight, and waste power. And then the extra handling required for 30 kV would force more weight and space wasting. And then there are safety concerns. I don't know what the OP really saw, but it wasn't a small copter running its motors from 30 kV. No way.
Sep
4
comment How is voltage increased from a battery?
@Alan: That 1 kV brushless motor won't be intended for battery operation. It is probably a large and high power motor so that the reduced current required at high voltage becomes a benefit.
Sep
3
comment The best way in which a man can pull a train
@bobie: I don't consider the question stupid. The problem is that you don't really understand forces and energy. This is context necessary for understanding answers to your question. That is something this site is not well suited to deal with. You seem to be wanting to understand, so I really think reading a introductory physics text would be a good move for you.