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Comment Re:Steampunk (Score 2, Interesting) 95

Miniaturized relays are interesting, but an inverter which operates at 0.0005 Ghz is less interesting. Somehow I don't think...

This is an incorrect and unfair assertion -- unfair by stating the switching rate in GHz.

In the real world, DC-DC inverters run below 1 MHz. From Wikipedia:
"Unlike a linear power supply, the pass transistor of a switching mode supply switches very quickly (typically between 50 kHz and 1 MHz) between full-on and full-off states, which minimizes wasted energy."


Comment Re:SEE! (Score 1) 271

Go USA! Five year in the sky totally kicks ass.

The LCD screen I'm looking at is made in China. It's a safe bet yours is too.

My laptop is made in China.
My cellphone is made in China.
My MP3 players are made in China.
My CS, DVD and Blu-Ray players are made in China.
My Roku box is made in China.
My media-center electronic equipment is made in China.
My Samsung HDTV is made in Korea.
My new refrigerator is made in China.
My Canon camcorder is made in Japan.
My cordless phone is made in China.
My USB hard drives are assembled in China.
My CFL replacement light bulbs are made in China.
My new kitchen appliances and serving ware are made in China.

My electric toothbrush is made in China.
And the list goes on...

Comment Re:Silly and presumptuous name... (Score 1) 325

Super Principia Mathematica
The Rage to Master Conceptual & Mathematical Physics

This book is dedicated with sincere gratitude and admonishing [sic] to the all wise (Omniscience)[sic], Omnipotent, and Omnipresent God the Father of us all; God the Son (Jesus) the Christ, and God the Holy Spirit for providing the wisdom, strength, and insight, and for being the author and finisher of my faith, making this work possible.

This paragraph is from the Acknowledgment.
http://www.superprincipia.com/First_Law_Of_Motion.htm/ Click Look inside, on page v.

Comment Re:Compatibility (Score 1) 279

Firefox lagged chrome mostly because firefox cares a LOT more about compatibility, ...

I wish Firefox could display my Netflix queue properly. It's impossible to delete an item that shows the DVD/Bluray listbox: the delete icon is lost.

I was forced to use IE but now there's the IE Tab Plus addon that invokes the embedded IE engine in a FF tab. Mediocre solution.

Comment Re:Attourneys General? (Score 1) 172

Seriously, can we stop with the French throwbacks, and say things the English way? What's wrong with General Attourneys?

Yes, that would make the singular and plural possessive cases easier.

For example, an AG and her staff are having lunch and the waiter arrives with sandwiches.

Should you tell him "that's the attorney's general ham and cheese"? Or should you say "that's the attorney general's sandwich"?

In TFA, should it be "the 33 attorneys' general lying venality"? Or "the 33 attorneys general's mendacity?"

Comment Re:Encryption (Score 1) 467

The problem with Truecrypt is that the volume is portable and they can run a dictionary attack against the passphrase at their leisure.

Then don't use a dictionary word or combination thereof.

TC uses a unique salt that is generated when you initially create the encryption key. The salt hashed with your password and the result is hashed again 1,000 times. Use of a salt prevents the use of a rainbow table. Hashing it 1,000 times grievously slows down any kind of brute-force attack.

The term "at their leisure" does not compare to even the most optimistic attack time frame.

Comment Re:Next up... (Score 2, Insightful) 95

"...faster than the wind, DIRECTLY DOWNWIND."

There's a bit of a cheat in the directly downwind assertion.

While it true that the vehicle is going directly downwind, its propeller is rotating in the wind. This causes to blade to experience the wind at an angle, just like a sailboat tacking into the wind. And in addition to the "lift" force perpendicular to the blade forcing the car forward, its rotation is used to drive the wheels.

Very clever nonetheless.

Comment Re:Wow, interesting! (Score 2, Interesting) 226

"Spinning faster = more velocity perpendicular to slope on the leading edge of the loop. It makes sense that it would flatten out."

Very good point. The back edge of the loop is being accelerated perpendicularly upward. IOW, the small length of rubber that's breaking contact with the table is yanked -- accelerated -- upward to a high vertical velocity. Therefore, it will rise higher that it does at a slower rolling speed. Like throwing a ball upward with a high velocity against gravity, it reaches a higher distance. In the case of the rubber loop the restoring force is tension in the rubber just ahead of the peak.

But there's that difficult-to-model problem of elasticity. I imagine the fast-rising rubber is pulled downward by tension in the bit of rubber just ahead of the highest point. Most of its upward momentum is opposed by the force of that stretched bit. And the kinetic energy, which is proportional to the square of the velocity, is transferred to mechanical energy (force X distance) stored in the stretched bit. Since KE is non-linear (square of velocity) you often get unexpected behavior. Here we get into differential equations!

Regarding the role of elasticity in the transfer of momentum and kinetic energy in the shaping of the rolling loop, it would be interesting to do an experiment using a non-elastic loop. An example would be a metallic chain. I expect the shape would be different.

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