Is the mpemba effect real?

Is the mpemba effect real?

Under our definition of the Mpemba effect, akin to the definition in the ‘original’ paper by Mpemba & Osborne8 (in which they documented “the time for water to start freezing”) we are forced to conclude that the ‘Mpemba effect’ is not a genuine physical effect and is a scientific fallacy.

What causes the mpemba effect?

Theories for the Mpemba effect have included: faster evaporation of hot water, which reduces the volume left to freeze. formation of a frost layer on cold water, insulating it. different concentrations of solutes such as carbon dioxide, which is driven off when the water is heated.

Does boiled water freeze faster?

If the water is initially hot, cooled water at the bottom is denser than the hot water at the top, so no convection will occur and the bottom part will start freezing while the top is still warm. This effect, combined with the evaporation effect, may make hot water freeze faster than cold water in some cases.

How cold is the mpemba effect?

New Scientist recommends starting the experiment with containers at 35 and 5 °C (95 and 41 °F) to maximize the effect. In a related study, it was found that freezer temperature also affects the probability of observing the Mpemba phenomenon as well as container temperature.

At what temperature does boiling water freeze instantly?

The air is not quite cold enough to freeze water immediately, which happens at about minus-42 degrees, Terry said. “It’s not snowing down,” he said. “You don’t see ice crystals falling to the ground. …

Does boiling water freeze quicker than cold water?

Hot water can in fact freeze faster than cold water for a wide range of experimental conditions. This phenomenon is extremely counterintuitive, and surprising even to most scientists, but it is in fact real. The phenomenon that hot water may freeze faster than cold is often called the Mpemba effect.

Does water freeze in space?

Does it freeze or boil? The surprising answer is it does both: first it boils and then it freezes! We know this because this is what used to happen when astronauts felt the call of nature while in space.

How long would a human last in space?

How long can you survive in outer space? Without a space suit, you’d lose consciousness in about 15 seconds, die after 90 seconds and freeze solid within 12 to 26 hours.

Do you freeze instantly in space?

Though space is typically very cold — most floating objects have a surface temperature of -454.8 degrees Fahrenheit — a person would not instantly freeze because heat does not transfer away from the body very quickly. On earth, heat can be transferred via convection, but outer space is mostly nothingness.

What happens to your body if you die in space?

If you do die in space, your body will not decompose in the normal way, since there is no oxygen. If you were near a source of heat, your body would mummify; if you were not, it would freeze. If your body was sealed in a space suit, it would decompose, but only for as long as the oxygen lasted.

What happens if an astronaut gets pregnant in space?

The primary problems with becoming and remaining pregnant in space are radiation and low-gravity environments. It’s important to understand both. Radiation can affect a man’s sperm count, rendering him infertile, possibly permanently. It can also harm a developing fetus.

Can astronauts fart in their suits?

As for your first question, farts that are within a suit made for exploration outside a craft like the heavy space suits get trapped with their host’s body inside the undersuit for a time. Therefore, the fart will not be smelled by the astronaut, although they may marinate in it for a time.

Do female astronauts shave in space?

Do astronauts shave in space? Both female and male astronauts shave in space and are provided with either an electric razor or a disposable razor. Most astronauts choose electric razors because of the scarcity of running water on the ISS.

Can you breathe in space?

Outer space is a vacuum. You cannot breathe in a vacuum because there’s literally no air to breathe, and if you tried, you’d be dead in about four minutes. Also, because space is extremely cold, your eyeballs could freeze solid, and even if you somehow survived, you’d be blind. There is no air.

Can Thor breathe in space?

By definition, Thor can’t “breathe” in space, as there’s no air there. However, as an Asgardian he can survive a very long time in space, without breathing. He had no trouble breathing while travelling between worlds in Thor 1 and 2. In the comics, though, he can survive space for long periods of time.

Can you light a fire in space?

Fires can’t start in space itself because there is no oxygen – or indeed anything else – in a vacuum. Yet inside the confines of spacecraft, and freed from gravity, flames behave in strange and beautiful ways. They burn at cooler temperatures, in unfamiliar shapes and are powered by unusual chemistry.

What planet can we breathe on?

Because the atmosphere of Venus is mostly carbon dioxide, oxygen and nitrogen — ordinary breathable air — would float. The air that’s holding you up is also the air that you can breathe. The lifting gas is your environment.”

Does Mars have oxygen?

Mars has only a thin atmosphere, with a surface pressure less than a hundredth of the Earth’s. Even worse, it is 96% carbon dioxide with only about 0.1% oxygen. The carbon monoxide would be unwanted, and would be vented back into the martian atmosphere.

Can we plant trees on Mars?

You can; you just have to compress the atmosphere into a greenhouse and plant them in soil that has been filtered of Mars’ perchlorate salt that’s toxic to higher life. a) The ground isn’t suitable for plants. There aren’t enough minerals and there is no water. And if there is liquid water, it’s extremely salty.

Does Mars have gold?

In addition, lithium, cobalt, nickel, copper, zinc, niobium, molybdenum, lanthanum, europium, tungsten, and gold have been found in trace amounts. It is quite possible that in some places these materials may be concentrated enough to be mined economically.

Can potatoes grow on Mars?

In The Martian, potatoes are successfully harvested after 48 sols (a Martian solar day – 24 hours 39 minutes long), but the success of the venture does not last: Watney’s potato-growing is put to an abrupt end as the front of his habitat blows off, exposing his entire crop to the Martian air.

Can we live in Mars?

However, the surface is not hospitable to humans or most known life forms due to the radiation, greatly reduced air pressure, and an atmosphere with only 0.16% oxygen. Human survival on Mars would require living in artificial Mars habitats with complex life-support systems.