- Education and Science
8 Amazing science facts that we live with, yet they sound like fiction
Science is the study of living and non-living possibilities. Most of such possibilities can sound ridiculous especially to the faint hearted, but they are hard science facts and we live with them every day although we easily ignore most of them
1. Hot water freezes faster than cold water
Supersized! Well, it is a fact and science can now explain why your hot cup of water will freeze faster than the cold one. According to science...
“Hot water seems to freeze faster than cold water, known as the Mpemba effect. The effect was named after the Tanzanian student who in 1963 noticed that hot ice cream mix freezes faster than a cold one. The effect was first observed by Aristotle in the 4th century BC, then later Francis Bacon and René Descartes. Mpemba published a paper on his findings in 1969.
Now a team of physicists from the Nanyang Technological University in Singapore, led by Xi Zhang, have found evidence that it is the chemical bonds that hold water together that provide the effect. Each water molecule is composed of one oxygen atom bonded covalently to two hydrogen molecules. These bonds involve atoms sharing electrons and are well understood. The separate water molecules are also bound together by weaker forces generated by hydrogen bonds. These forces occur when a hydrogen atom from one molecule of water sits close to an oxygen atom from another.”
The team suggests it is these bonds that cause the Mpemba effect. They propose that when the water molecules are brought into close contact, a natural repulsion between the molecules causes the covalent bonds to stretch and store energy. When the liquid warms up, the hydrogen bonds stretch as the water gets less dense and the molecules move further apart.
2. You collide with space debris every day
Space is quite out of reach for many of us, and for most, it is a subject of science fiction. However elements from space are within our atmosphere. Cosmic debris falls from space in huge amounts daily and we are in contact with it without knowing. Science has it that;
“Dust particles, originating from comet's orbiting the Sun, frequently enter Earth's atmosphere where they collide with air molecules at speeds between 40 000 and 260 000 km/h (24 854.8 and 161 556.5 mph) and generate flash heating followed by melting and evaporation of the particles.
"Sometimes this dust is visible as meteors, which is the case of dust particles greater than 2 mm. But most of the dust mass entering the atmosphere is so small that it can only be observed using specialized meteor radars," explained John Plane, the CODITA Project Lead.
However, so far, very little has been known about exactly how much dust enters the atmosphere and what impact it has. It has been estimated that between 3 and 300 tons of particles enters our planet's atmosphere on a daily basis.”
3.The earth is constantly trying to fly you into space.
Sounds crazy, right? But it is science fact. The earth is spinning really fast and is revolving around the sun at such a high speed that all objects that are not rooted should be flying off into space. Think of it like riding a merry go round. If not for being held in place by security straps, you’d be flying off of it in a matter of seconds.
“The Earth is spinning around its axis. At the equator, the Earth's surface moves 40,000 kilometers in 24 hours. That is a speed of about 1040 miles/hr (1670 km/hr or 0.5 km/sec). This is calculated by dividing the circumference of the Earth at the equator (about 24,900 miles or 40,070 km) by the number of hours in a day (24). In addition, the Earth revolves around the Sun at a speed of about 18.5 miles/sec (30 km/sec).”
But thanks to gravity, everything including human kind is firmly secured onto the earth’s surface.
4. Water is sticky and can act like glue
Sounds like fiction, but in fact it happens in real life but on a small scale. Water is one of the most unique elements in the universe and many of its properties still puzzle scientist. According to a new study, when water vapor condenses in a Nano-sized space between two surfaces, the liquid behaves more like solid ice than liquid water, even at room temperature. This solidification causes water to exert such a strong friction force that it “acts like glue,” according to a new study.
“Although in many cases, water acting as glue on the Nano scale is a nuisance, there are also situations where one can take advantage of the stickiness on this small scale,” said Frenken. “On a macroscopic scale, we all know how dental prostheses that can stay in place via the action of bridging water. In this case, however, the water is still completely liquid because of the thickness of the water layers. In the laboratory, we often use capillary condensation to pick up light objects, simply touching a small object with a thin wire, instead of using tweezers. A capillary neck forms between the object and the wire, gluing the two together.” This “nuisance,” then, may lead to more useful applications, in addition to the problem it identified.”
5. The air pressing down on you is as heavy as a small car
Air is invisible and we speed through it daily with minimal encumbrance. But air is in fact quite heavy and all this weight is crushing down on you, but surprisingly your body can handle it. The question is how heavy is air?
According to science...
“Even though they’re too tiny to see, all the molecules of air in the atmosphere above your head weigh something. And the combined weight of these molecules causes a pressure pressing down on your body of 10,000 kg per square metre. This means that the mass of the air above the 0.1 square metre cross section of your body is 1,000 kg, or a tonne.
If you tried to lift a small car, you’d certainly notice it, so why don’t we notice that there’s a tonne of air pressing down on us? Well, the air exerts this force in all directions, so as well as pushing down on us; it also pushes up and balances out the force on our bodies so that we don’t collapse"
6. Water is the only substance for which the solid floats in the liquid
Water is the only substance that exists in all forms of matter on earth. That is; liquid, solid and vapor. But water is a little more special than that. It is the only substance which when frozen, floats in its liquid form.
“Water is almost the only substance in the universe for which the solid floats in the liquid! http://www.americangeosciences.org/educ ... er-special
7. Solid ice always has a thin layer of liquid water, which makes it slippery. But scientists have never figured out why.
Science has answers to many things, but this is one of those that still remain elusive. You probably know that walking or driving on ice can be a daunting task. As obvious as it seems that ice is very slippery, science has never been able to explain the reason behind this phenomenon. Although it is understood that the slippery property is cause by a thin layer of liquid water present on the surface of solid ice, the reason as to why this thin layer of liquid water persists is not yet fully understood.
“A century and a half of scientific inquiry has yet to solve this one. It's clear that a thin layer of liquid water on top of solid ice causes the slipperiness. A fluid's mobility makes it difficult to walk on, even if the layer is thin. But there's no consensus as to why ice—unlike most other solids—has such a layer.
Scientists long reasoned that, since water has the unusual property of being less dense as a solid than as a liquid, its melting point can be lowered with an increase in pressure. While this is true, even the sharpest of skates raises the melting point by only a few degrees. The pressure theory doesn't hold water unless the ice is pretty warm already. Something else must be going on.”
8. Water will take longer to vaporize when in contact with a surface at 200°C
It is common knowledge that water will start evaporating into steam as soon as it is heated, and will boil at 100°C. However when water droplets come into contact with a surface twice the boiling temperature, the droplets “dance” around in the hot surface as the vapor propels it in different directions. This is a common site in the kitchen when we try to taste how heated the pan is by sprinkling a few drops of water. Although it is usually taken at face value, there is plenty of science to the show and it is referred to as the ‘Leidenfrost effect’. Science has it that;
“The process of film boiling is attributed to the doctor and theologian Johann Gottlob Leidenfrost (1715-1794) who first described the effect in a manuscript titled A Tract About Some Qualities of Common Water. The most common occurrence of the Leidenfrost effect can be found in the kitchen, when a droplet of water is placed on a hot frying pan. If the pan is heated to the Leidenfrost point, about 200°C, the water evaporates so quickly that a thin layer of vapor forms between the pan and the water droplet, protecting the water from the burning hot pan. The vapor also causes the water droplet to “dance” around in the pan as the vapor propels it in different directions. The droplet will of course evaporate over a certain amount of time, but it will take significantly longer than if the pan were heated to a temperature above boiling, but below the Leidenfrost point.”