Answers to 9 Questions That Have Been Nagging Us for Years

Is it possible to disinfect a wound with seawater and to cool down a room with an open fridge? Should pregnant women be afraid of cats? Is it possible to suppress a yawn? Sometimes we have immediate answers to these questions because we were once told so by our parents or someone else. But don’t be too trusting. This article will help you find the answers to questions that may have been nagging you for years.

1. Can an open fridge cool down a room?

A fridge cools because compressed gas decreases its temperature when it widens. If you open a door, the system will work more actively to keep the temperature inside on a necessary level. Which means that the engine will emit more heat into the room because its efficiency of energy conversion is always less than one.

So, an open door of a fridge will only warm up the room. But if you manage to turn the back side of a fridge to an open window, you’ll get an air conditioner.

2. How do fireflies glow?

Fireflies have an organic molecule in their body called luciferin. It reacts with the molecule of adenosine monophosphate (the source of energy for all organisms), a special ferment, and oxygen. The resulted substance contains oxyluciferin. It has an electron in the excited state, and this is the key to why fireflies glow.

3. Why are sunsets of golden and red colors?

During a sunset or a sunrise, sunlight reaches a certain place of Earth at an acute angle, being almost parallel to it. That’s why light passes through the atmosphere longer than during the daytime. Spectral wavelength shifts to the red diapason where the wavelength is longer.

4. How does a UV lamp harden nail polish?

Nail polish is a polymer which is a molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetitions of units derived. Nail polish contains a thinner thanks to which it has a liquid texture and can be easily applied to a nail. When in the open air, the thinner evaporates. However, with gel, this process is too slow and ineffective, and here UV drying becomes handy.

UV radiation helps break the links of molecules and build a longer chain of them. Due to this chemical restructuring, polymer hardens. By the way, different gels demand different wavelengths, so UV light can’t dry everything.

UV light can’t speed up the process of drying regular nail polish. Unlike gels, it doesn’t contain photoinitiators which absorb UV radiation and launch polymerization.

5. Is it dangerous for a pregnant woman to be in contact with a cat?

It is true that cats can get a virus called toxoplasma when eating raw meat. It is not dangerous for adults — half of the people on the planet carry this virus and don’t even know about it. However, this virus can be dangerous to a fetus if a pregnant woman got infected with it during her pregnancy but not before it.

But you can get infected only through a cat’s excrement, not by contacting a cat itself. That’s why you need to clean a cat’s toilet in gloves and thoroughly wash your hands afterward (or even delegate this task to your partner), then toxoplasmosis is not dangerous to you. You can pet your cat as much as you want to. By the way, this virus can’t be transmitted through bites or scratches.

You have a greater chance of getting infected with toxoplasmosis if you eat raw meat or work with soil in your garden. So, forget about gardening during your pregnancy.

6. Why does oil splutter from a frying pan?

Oil splutters only if you pour it on a wet frying pan or if you put wet meat or vegetables there. The boiling temperature of olive oil, for example, is 3 times higher than the one of water.

This immediate expansion forces the oil out which leads to splutters.

7. Does seawater have antiseptic qualities?

Deep-sea water is an excellent remedy to fight infections. However, a huge amount of bacteria and viruses live on the surface of oceans and seas. Bart Currie, an expert in contagious diseases, saysthat you must be careful with sea water that comes from tropical zones, places near sewage, mines, farms, and industrial zones, in general.

Your chances of getting infected depend on your immune system. If you are a healthy person, your chances are rather low. Still, if you have scratches or wounds, it’s better to treat them with antiseptic when you get out of the sea.

8. Why does squinting improve your vision?

The eyeball of a long-sighted or short-sighted person is slightly deformed. As a result, their vision loses its focus and they see blurred objects. Squinting removes upper and lower streams of light which reach the eyes at an angle. At the same time, the light going in the center of the eye doesn’t need refraction, so we can see a bit better.

The other reason is that squinting (which means tensing the upper and lower eyelids) leads to a certain change of the shape of your eyeball and that helps improve your vision temporarily, as well.

9. Why is yawning contagious?

Andrew C. Gallup, a psychologist from the Department of Psychology State University of New York at Albany, concluded that yawning helps cool down an overheated brain. He asked the participants of his study to apply ice to their forehead when they wanted to yawn, and their desire to yawn really passed.

Gallup explains collective yawning by the necessity of protecting yourself against danger. If an animal yawns, this means that its brain doesn’t work at its full capacity and the other members of the flock should compensate the loss of its attentiveness so as to not let a potential threat to approach them. So, they yawn in return to cool down their brain and make it function at an optimal level.

Do you have questions which you always wanted to find answers to, or maybe you have answers to some other common questions? Tell us in the comments below and we’ll try to meet your requests in our future articles.

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