More intresting trivia

Some interesting scientific and historical items I picked up in recent readings:

1. CHARLIE CHAPLIN:  Apparently Charlie once came in third in a Charlie Chaplin Look-alike contest in Monte Carlo.

2. WHO REALLY FLEW FIRST?  Contrary to popular opinion, the Wright Brothers were not the first to achieve powered flight. The first was, apparently, a Frenchman, Clement Adler, who flew a powered craft some 50m. (Some 13 years before the Wright Brothers).  The Wright Brothers were the first to achieve controlled powered flight. (true to form, whatever an American invents is, naturally, the more important than anything anyone else may invent).
   However, the Wright Brothers were apparently, (and I haven’t confirmed this), the first to realize that the propeller is in fact a rotating wing, and as such it generates “lift” just as a wing does.  Therefore since the tips move faster than the inner part of the propeller blade, the pitch can vary throughout the length to even out the “lift” over the length of the blade.

 

3. THE FIRST VOICE BROADCAST:  The first voice modulated radio broadcast was made by a Canadian. Tom Edison had hired a Canadian physicist named Reginald Fessenden who, in 1897, wanted to experiment with broadcasting the human voice. Edison, however, discouraged him, saying that such a thing was less likely than man’s chances of jumping over the moon. Nevertheless, Fessenden made the first voice radio broadcast on Dec 23, 1900.

4. Lord Kelvin, while president of the Royal Society, proclaimed that “X-Rays will prove to be a hoax” and also that “Radio has no future”.

5. SCRATCHES ON CD's:  found out an interesting fact about CD’s.  I’ve always wondered why scratches don’t come through as pops or dropouts in the audio. The way it works is the two audio tracks are sampled 44,100 times per second each and the samples are turned into digital codes representing the amplitude of the sample. You would therefore expect that a scratch would ruin enough of the coded samples to cause either a dropout or a pop in the audio. It doesn’t.
   
   The reason why it doesn't is that the crafty buggers who designed it, realized that the samples don’t have to be put on the track sequentially….. they can, instead, be “interlaced” out of order so that a scratch that is wide enough to interfere with several codes in succession will in fact be spread out over several waveforms and will not be detectable.  They also, of course, included three error correcting bits in each sample which allow the reader to detect and sometimes to actually correct, an error. By the way, the track on a CD, starting from the inside, is actually about 3 ½ miles long and the speed of the disc changes from about 500 rpm to about 350 rpm at the outer edge so that the bits/second is constant.

6. COMPUTER CHIP LIFE:  Modern computer chips apparently have an expected life-span of about 5 years continual service.  There are three mechanisms responsible:
   ELECTROMIGRATION: which causes atoms in the metal to be swept along like pebbles in a stream to be deposited where they shouldn’t be.
   OXIDE BREAKDOWN: weak spots developing in the insulating oxide layer and causing shorts.
   HOT-CARRIER INTERACTION: where overenthusiastic electrons may punch through the oxide layer.
   Older chips with larger internal components can apparently last many decades.

7. SPAM:  The word “spam” representing junk e-mails, comes from a skit performed at the final Monty Python Flying Circus show of 1970 wherein they insert the word “spam” throughout the skit.

8. BALL POINT PENS: Do you know why ball point pens leak when they get wet?  Did you know that they do? Well, the reason is that when you finish writing the ink left on the ball immediately dries, form-ing a seal. If, however, the pen gets wet, the seal is broken and the ink leaks out.

 

9. SUPERGLUE: Apparently scientists are not really sure how superglue works. One theory is that it is because of “van der Waals” forces, which are forces between molecules resulting from the interaction of their polarities.  What they do know is that the cyanoacrylate (superglue) reacts with water to form long chains that coil around each other and bond together to form a hard resin. That’s why it sticks to skin so well and why it is used to detect fingerprints.