Silly-sounding question, maybe, but with several interesting answers. People tend to put up with fishy smelling fish in markets and restaurants because they’re thinking, Well, what else should it smell like? But fish needn’t smell like fish at all. Not if it’s perfectly fresh. When they’re only a couple of hours removed from the water, […]
The measurement of rainfall is fairly straightforward, but snowfall presents problems that make measurements somewhat arbitrary. For rain, the meteorology department at Pennsylvania State uses a simple cylindrical tube to catch it. The amount that falls in a given period is poured into a smaller cylindrical tube that is carefully gradated and measured with something […]
Many insect species swarm, both the beneficent (like honeybees) and the irritating (like mosquitoes). In many cases, springtime swarms consist of groups of males all looking for suitable mates. Pheromone signals probably keep the group together. As insect mating, egg laying, and hatching tend to take place in synchronized waves, it is not surprising that […]
FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS The fact that most people can only see three Fs instead of six would only be strange if reading was entirely phonetic. In reality, several methods are used to get meaning from print, and the most common of these […]
Yes, there are such plants, called halophytes. Some are natural species that grow well when the water they get has a high salt content. Others are species that scientists are tailoring for the purpose by selective breeding or crossbreeding for salt-tolerance genes. Halophytes include grasses, shrubs, and trees. Some are edible crops suitable for areas […]
Whether it’s a dog, cat, human or cow mouth, they are all probably pretty similar in terms of cleanliness or dirtiness. It’s certain that there’s not a whole lot of difference as far as bite wounds are concerned. Mouths contain germs that can cause infections, and it would be dangerous for a child to bite […]
Enrico Fermi was born in Rome, Italy, in 1901. His family was poor, and Fermi was so shy that he had few friends. He would spend his time in used bookstores buying as many books as he could on his favorite subjects, math and physics. Throughout his education, he was far ahead of his classmates […]
Yes, there is a much simpler way, and it’s a shame they don’t teach it in school. Once those complicated formulas with all their parentheses and 32s got into a textbook somewhere, they seem to have taken on a life of their own. Here’s the simple method: To convert a Celsius temperature to Fahrenheit, just […]
Oh, those chemistry majors. The “Maillard reaction” refers to the chemical changes that occur when you make toast. The name honors L. C. Maillard, the French chemist who in 1912 first discovered that bread’s starches and sugars caramelize into intense new flavors when toasted. Other foods can occur in many other foods including, Biscuit, Malted […]
Haven’t we become a bit of a paranoid society? Our drugstores and supermarkets cater to our fears (or do they encourage them?) by displaying dozens of antibacterial soaps, sprays, gels, lotions, hand washes, body washes, wipes, deodorants, and mouthwashes. Television commercials strike terror in our hearts by suggesting that there might be a germ or […]
What Else Did Antonie van Leeuwenhoek Discover With His New Microscopes Besides Single Celled Organisms?
In 1610, the Italian astronomer Galileo turned the telescope toward the skies and opened up a new universe to exploration. Antonie van Leeuwenhoek did the same with his microscope and a different universe. In a long life of careful observation and recording, he made many discoveries. Leeuwenhoek studied his own blood and discovered red and […]
Strings of lights do not harm a tree unless it is brought inside in a pot and exposed to warm dry air and then suddenly taken back outside into the cold, or unless the lights are actually hot enough to cause burns. Light does affect the growth cycle of trees, but chiefly in combination with […]
Why Do Most People Aim a Rifle With One Eye Closed and Who Discovered the Phenomenon of Binocular Rivalry?
Not everyone does, but those who do, do so because of a phenomenon called binocular rivalry. If you look through a sight with the left eye, what you see is not identical with what you see with the right, and the two images compete, rather than blending, as they normally do when you look at […]
Joseph Priestley was born in Leeds, England, in 1733. Priestley was raised by an aunt who was a member of a religious group called the Dissenters. The freethinking group rejected many of the beliefs of the Church of England and gave Priestley a spirit of rebellion that would stick with him throughout his life. Priestley […]
Around A.D. 145 in the Greek city of Pergamum, a father had a dream that his son Galen should become a physician. Dreams were very important to the Greeks of the ancient world because they were thought to be inspired by the gods. The father immediately enrolled his 16 year old son in Pergamum’s medical […]
James Clerk Maxwell’s findings about electromagnetism in the 1870s and Hertz’s discovery of radio waves in the 1880s made Nikola Tesla think that the possibilities of electricity were endless. Tesla’s next research was on high frequency electricity, but he had a problem. Even his advanced AC generators could only generate a current of about 20,000 […]
It’s a challenge, all right. DVDs use similar material and manufacturing processes, but there are several differences. Part of the solution was making the bumps that carry data smaller and jamming them closer together, making the “groove” of a DVD 7.5 miles long, more than twice what you get on a CD. But wait, there’s […]
The water in a water bed will indeed settle down to the same temperature as everything else in the room, including a conventional bed. But you would still feel colder on the water bed. It has to do with the fact that water conducts heat away from your body a lot more efficiently than other […]
The cloudiness is a mass of tiny air bubbles, air that was dissolved in the water and expelled when the water froze. You can see the individual bubbles through a magnifying glass. There is always some air dissolved in any water that has been exposed to, well, the air. For this, the world’s fish are […]
It’s one of life’s little ironies. Sailors do hard, often dirty work, yet with all that water around they can’t bathe or wash their clothes with soap. Not with ordinary soap, anyway. There is a special soap called “sailors’ soap” that works in salt water. But first let’s see why the ordinary stuff doesn’t. It […]
No, smarter people’s brains are not bigger and heavier than dumber people’s brains. There’s no apparent connection between brain size in humans and their intelligence. If that were the case, the average man would be 10 to 12 percent smarter than the average woman because men have larger brains by about a third of a […]
Sorry, but yes. Not actual fragments, but individual molecules, molecules that have evaporated from the “stuff” and have floated through the air to your nose. But don’t get sick at the thought. It takes only an incredibly small number of molecules to be detected by humans as an odor. And the molecules aren’t even molecules […]
You can’t see any man-made object on earth from the moon. It’s too far of a distance from earth to see anything. If you look at pictures of astronauts on the moon with the full Earth behind them, you can see why, Earth from the moon doesn’t look much bigger than the moon looks from […]
Why Does a Beer or a Coke Poured Into a Dry Glass Froth Up Faster Than When Poured Into a Wet Glass?
Beer, sparkling wine, a Coke, and other fizzy drinks are liquids which are supersaturated with gas. Although thermodynamics favours the gas bubbling out of the dissolved state, bubble formation is unlikely since bubbles must start small. The pressure of these tiny bubbles can reach about 30 atmospheres in a bubble only 0.1 micrometres in diameter. […]
Why Does Bacon, Ham, or Pork Sometimes Have a Greenish Color When Stored In the Fridge and Is It Poisonous?
A greenish iridescent sheen is often found on foods containing traces of fat in water. When it is cool this mix separates out microscopically into a film, like oil on a wet road. In some types of cold meats, such as sliced silverside of beef or some hams, you may see a handsome opalescence. The […]
Well, yes, but British royalty (as noted above) don’t always do things because they make sense. The original marathon from the first modern Olympics in 1896 was actually based on physical landmarks. It began at Marathon Bridge and ended at Olympic Stadium in Athens. This gave it a distance of 24.85 miles, or an exact […]
Although most apples will float, they can vary somewhat in their aquatic stabilities. Buy samples of a few varieties several days before the party and test them. Then go back to the store and load up on the best floaters. Asking your guests to bob for apples that sink to the bottom would severely compromise […]
How High Would a Bullet Go If You Fired a Gun Into the Air and How Long Would It Take To Hit the Ground?
Firing handguns into the air is commonplace in some parts of the world and causes injuries with a disproportionate number of fatalities. For a typical modern 7.62 millimetre calibre bullet fired vertically into the air from a rifle, the bullet will have a velocity of about 840 metres per second as it leaves the muzzle […]
Before we get any further, note well: Water must never be used on an electrical fire or on an oil or grease fire. Reasons: Water conducts electricity and can lead it elsewhere, perhaps to your very own feet. And because water won’t mix with oil or grease, it just scrambles it around and spreads the […]
How Do Placebos Work, What Does It Mean In Latin, and What Is the Difference Between a Placebo and a Nocebo?
Placebos are substances with no pharmacological properties, such as sugar or dummy pills. The word placebo means “I shall please” in Latin, and was first used in a medical context in the 18th century. They are widely used as a control in experiments to test the effect of medicines, and are made to look and […]
There are treatments for vitiligo that are at least partly effective in many cases, but its cause is still under study. A prominent theory is that an autoimmune reaction is involved. The condition may also be associated with certain ailments, including thyroid disorders, and may flare up after injury, stress, or severe sunburn. Patches occur […]
They work somewhat the way an old-fashioned stereopticon viewer (holding two slightly different photos) works. Each eye focuses on a separate image, but the brain combines them into one image that gives the illusion of depth (the third dimension) in addition to width and height. It does this by matching up the similarities and adding […]
There is no maximum temperature, because there is no limit to the amount of energy you can put into anything. Absolute zero, minus 273.15 degrees Centigrade, minus 459.67 on the Fahrenheit scale, is theoretically the temperature at which all molecular activity ceases. It represents an absence of energy. There is the concept of a lowest […]
The very best way to get ketchup out of the bottle, as was once memorably demonstrated by David Letterman, is to grasp the bottle firmly around the bottom and swing it round and round over your head, like a lariat. Of course, the ketchup will splatter all over the walls, but you asked only how […]
What Is Tia Maria and How Does the Cream On the Surface of Tia Maria Create Toroidal Cells and Patterns?
Tia Maria is a coffee liqueur made originally in Jamaica using Jamaican coffee beans. It is beautiful to watch patterns form on the layer of cream on a Tia Maria, and how different patterns form in layers of cream of different thickness. This is all caused by convection. Convection is the bulk movement of fluid, […]
It’s a good question. You’d think that a rocket’s exhaust has to push against something, like a paddle needs to push against water to propel a canoe. But in reality, a rocket doesn’t need to push against the atmosphere to fly. What it’s doing is essentially pushing against the inertia of the rocket exhaust. But […]