Friday, February 20, 2015
1. This time last week, my daughter made
my Valentine's Day a day early. After leaving her in the family
room to perform a short chore, I heard her calling for
"What is it, Pumpkin?", I said.
"I have a secret!" she said, gliding by on her scooter in the next room and wearing a big grin.
"What is it?"
"I love you!"
2. Another week, another myth bites the dust. Remember that high-school chemistry lab demonstration of sodium causing an explosion when dropped into a beaker of water? You probably didn't get a complete explanation for why that occurred:
High-speed cameras revealed a vital clue to what was fuelling the violent reaction in the early stages. The reaction starts less than a millisecond after the metal droplet, released from a syringe, enters the water. After just 0.4 ms, "spikes" of metal shoot out from the droplet, too fast to be expelled by heating. What's more, between 0.3 and 0.5 ms, this spiking droplet becomes surrounded by a dark blue/purple colour in the solution.There is a video at the link showing what the researchers found, and explaining the Coulombic explosion that results.
3. Apparently, phantom traffic jams were finally explained a few years back:
...Measurements on various motorways in Germany and Japan have shown that free-flowing traffic becomes congested when the density of cars reaches 40 vehicles per mile. Beyond that point, the flow becomes unstable and stop-and-go waves appear. Because it's founded in human reaction times, this happens regardless of the country or the speed limit. And as long as the total number of cars on the motorway doesn't change, the wave rolls backward at a predictable 12 mph.Experimental video appears at the above link.
Remember that the next time you reach the end of a long jam on the highway, only to find no apparent cause!
4. These geeky pick-up lines (courtesy of Snedcat) are all priceless. I especially like the seventh.