Luckily for deep-diving whales, they have an entirely different system from that of humans for handling the air they breathe before diving and their oxygen needs while diving. When pressure is released on gases dissolved in the blood, the bends result. Whales are taking in air breathed at the surface and carrying it to the […]
Why Do Honeycomb Shapes Appear When Cooking Oil Is Heated On a Pan and What Are Bénard Convection Cells?
The honeycomb cells observed in heated cooking oil are known as Rayleigh-Benard convection cells. At low temperature differences between the bottom and the top of the oil, the heat is dissipated through ordinary thermal transport, or collision of individual molecules, and no macroscopic motion can be observed. At greater temperature differences, convection, a collective phenomenon […]
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 […]
The brain’s activities do expend energy, and fuel is burned, but in very small amounts. In the sense of actually breaking down fatty tissue so that one might lose weight, thinking would play a very minor role. Extensive studies of brain function have been made and the varying levels of energy use at different levels […]
Even though they are members of the same chemical family, there are vast and crucial differences among the alcohols, and it can be a matter of life and death to be aware of them. Alcohols are a large family of organic (carbon-containing) chemicals that are related in two ways: their molecules contain one or more […]
Thermotropic liquid crystals makes a mood ring change colors. They’re little crystals that change molecular states when the temperature changes. When their molecular states change, the crystals’ ability to absorb light also changes, meaning the color you see will change, too. The ring picks up body heat from your finger, and transfers it to the […]
Brain size is not generally seen as a reflection of intelligence in dogs or in other species. That is evident if you compare other species with different brain sizes — for example, elephants and people: People are far more intelligent despite the huge disparity in physical size. Intelligence has more to do with the development […]
The National Institute on Alcohol Abuse and Alcoholism of the National Institutes of Health estimates that alcohol is cleared at a rate of approximately one hundred milligrams per kilogram of body weight per hour. That’s about half an ounce of pure alcohol every two hours. So if a person ingested approximately three drinks in a […]
Seawater appears blue because it is a very good absorber of all wavelengths of light, except for the shorter blue wavelengths, which are scattered effectively. The light attenuation is caused by the combined absorption and scattering properties of everything in the water, along with the water itself. Changes in the sea’s color are primarily due […]
How Do Bacterial Diseases Develop Antibiotic Resistance and How Does Antibiotic Misuse Create Superbugs?
A drug that kills bacteria is referred to as an antibiotic. Many antibiotics have been developed since Ehrlich founded chemotherapy and Alexander Fleming discovered the first antibiotic, penicillin, in 1928. There is a growing problem, however, with the use of antibiotics. They have been overused. Just as humans develop immunity to diseases, bacteria develop immunity […]
The joystick predates computers by decades. It has been a part of airplanes almost since their introductionits first known reference dates back to 1914. An airplane joystick works much the same as with computer gamesyou pull or push it, or lean it to the side, to control direction of movement. Where did it get its […]
The first artificial heart valve was implanted in 1952 and used a tiny plastic ball to alternately open and close the blood flow. One problem was that when patients opened their mouths, clicks from the valve were annoyingly loud. The first artificial heart was made of Dacron and was in a Texas man’s chest in […]
It’s not the rain itself that you smell, but just about everything else. Almost everything smells a little stronger when it’s about to rain. Stormy weather is usually preceded by a drop in atmospheric pressure, or what the TV weather people like to call “barometric pressure.” (Is that what you feel when you’re struck by […]
Most gulls do not have feet that are adapted to perching in trees and clinging to tree branches. Most have slightly webbed feet that help them move about in the water, so when they are on land, they do better walking on rocks or soft surfaces like sand. Pure probability also puts gulls on the […]
Why Does Ice Float On Water and Why Is Ice the Only Non-Metallic Substance To Expand When it Freezes?
Ice floats because water molecules occupy more space in the solid state than in the liquid state, so that a given volume of ice is lighter than the same volume of water. The way molecules fit together in ice crystals is not as compact as in water. They don’t change size, it is just the […]
The technology in a fax machine is pretty simple. A bright light reflects off the document as it passes along a strip containing hundreds of tiny photocells. If a white area of the page passes below, the photocells convert the light shining off the document into electricity. If the area is black, the photocell generates […]
Why Do the Remains of Buildings From Ancient Civilizations Sink So Far Below the Surface of the Earth?
Although archeologists tend to uncover things, that is not necessarily because ruins have sunk beneath the surface of the earth. Instead they are usually covered over with newer buildings or natural deposits of sand and debris. There are exceptions, for example, in Mexico City, the Aztecs built temples on a lake bed, where they did […]
How Are Eggs With Two Yolks Formed, What Causes Double Yolked Eggs, and What Is the Best Way To Check an Egg?
Eggs with two yolks are a natural phenomenon over which we have no control. Double yolk eggs are larger than those laid by the majority of the flock and are set aside to be tested individually. Demand for double yolkers far outstrips supply and we need to be very sure that they do in fact […]
It is a common misconception that the white droppings produced by birds are feces. In fact, they are urine. Birds excrete uric acid rather than urea because it is an insoluble solid. This way they avoid wasting water when urinating, just one of their adaptations for a good power-to-weight ratio. The white material that comprises […]
Meteorologists love to tell us the dew-point temperature, even though few of us know what it is and even fewer of us care. But as long as I’m this deep into water vapor, I might as well explain that too. The dew point, or dew-point temperature, is the temperature below which the liquid-vapor balance of […]
Most land line phones would work in a power failure, just not cordless ones unless there’s a battery backup system. The telephone network system provides its own power system through the phone lines, so that your basic corded phone will often work even when your lights won’t. It’s a pretty good system, but it gets […]
There are several ways it can rain instead of snow even when the temperature is below freezing. It helps to think of the air from clouds to groundas a series of layers, each with its own temperature, and each with the ability to affect falling precipitation. For example, the cloud may be below freezing temperature, […]
It’s a plausible theory, on the face of it. Dust does seem like some sort of weird alien thing, in that it appears from nowhere and doesn’t seem to be the same dirt, sand, and other stuff you find blowing around outside. Furthermore, it’s a known fact that about a thousand tons of cosmic dust […]
A higher ratio of wastes to water turns urine a bright yellow color, which explains why the first urine in the morning is often quite a deep yellow. If your urine is a very faint yellow, it generally means you’re well hydrated. If your urine is dark, you’re probably dehydrated. Eating different types of food […]
On November 3, 1957, less than a month after its first ever space launch, the Soviets sent up Sputnik 2, complete with a dog named Laika. She didn’t survive in space for very long. Conflicting accounts put the number of days at somewhere between four and seven, but that was it. The Soviets, rushing to […]
Gibraltar stands as the northern gateway to the Mediterranean Sea, and has historically been a much-coveted fortress for observing all the movement in and out of the area. Despite its history as an impenetrable fortress, the Rock of Gibraltar consists almost entirely of soft gray limestone with a touch of shale thrown in for good […]
Absolutely. And during the autumnal equinox as well. And on Tuesdays in February, and anytime during the fourth game of the World Series when the count is three and two on a left-handed batter. Get the picture? The point, of course, is that equinoxes have nothing whatsoever to do with balancing eggs. But old superstitions […]
That’s a common belief that just doesn’t hold water, so to speak. First of all, the ocean’s surface isn’t exactly what you’d call a mirror. And second, how come it’s a much darker blue than the sky? No, the world’s oceans really and truly are blue, many different shades of blue (ask any sailor), depending […]
The assumption that a bird’s tail functions only as a horizontal surface is erroneous. A bird also can twist its tail from left to right and downward, so it acts almost as a braking system that allows it to bank into turns. Some birds are better at this than others. Some hawks in the group […]
What Is the Best Way To Make Shandy and Why Does Pouring Lemonade After the Beer Make It Fizz and Overflow?
Shandy, also known as shandygaff, is beer flavored with carbonated lemonade or ginger ale. If you pour lemonade and beer into separate glasses you will notice that only the beer forms a head. That is because beer contains surfactants, proteins, and other long-chain molecules that help liquid films to form and stabilize bubbles. Lemonade bubbles, […]
Why Do Ornamental Cactus Plants Release Hundreds of Spiders and How Are Tarantulas Dangerous Spiders?
The story about an ornamental cactus releasing spiders is a popular myth. Such an event is particularly unlikely to involve tarantulas, which might possibly lay eggs or build webs on, but not in, a cactus plant. Tarantulas live in burrows in the ground, especially the female, which rarely moves around on the surface. Tarantulas take […]
Why Does Liquid Flow Down the Side of a Container If You Pour It Too Slowly and What Is the Coanda Effect?
When a carton of liquid is tipped during pouring, the free surface of the liquid in the container is raised relative to the opening. This creates a pressure difference between the free surface and the opening, which forces fluid from the carton. In addition to this pressure force, there are also surface tension forces acting […]
It’s not true that adding salt to the water before boiling eggs prevents the eggshells from cracking. Salt (sodium chloride) has no effect on eggshells (calcium carbonate), either chemically or physically. An eggshell can crack when there is a sudden temperature difference between a cold shell and hot water. The heat makes the shell expand […]
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 […]
It can be embarrassing when stomachs make noises, but they have their reasons; a lot is going on in there. When your stomach is empty, and there’s nothing for the stomach acid to do, it doesn’t just go away. It churns and produces gases as it bubbles and waits, impatient for you to feed it. […]
Avogadro’s study of gases and atomic weights led him to two conclusions. First, the atoms of many elements actually occur in groups of two or more, called molecules. A molecule, which means “mass” in Latin, is the smallest unit of a substance that has all the chemical properties of that substance. For example, two oxygen […]