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What lives in the area of a nuclear power plant?
I wonder if there are any animals living in the area of a nuclear power plant and what do they look like ...
The site of a nuclear power plant usually occupies an area of approximately three square kilometres and includes, from the animal's point of view, a number of attractive biotopes. There are grassy areas for insects and small animals, bushes, roofs, ledges and pipes providing safe shelters and nesting opportunities or open pools under cooling towers for aquatic creatures ...
Why does atmospheric pressure change and how does it affect humans?
Atmospheric pressure varies mainly with weather and also with altitude. Because atmospheric pressure is the pressure caused by the weight of the air column, the higher we are, the smaller the height of the air above us and thus the weight of the air column is smaller and therefore the atmospheric pressure too ...
What is a photovoltaic panel doing with the sun shining on it when no one is drawing electricity from it?
The photoelectric phenomenon inside the photovoltaic panel takes place every time the sun's rays fall on it ...
A photovoltaic cell is a thin wafer of silicon modified to function as a semiconductor photodiode. When a photon hits its surface, it transfers its energy to one of the electrons, which is released from its electron shell. When enough electrons accumulate, a voltage is generated at the output of the photovoltaic cell ...
How is gravity produced on a spaceship?
Gravity is a property of all material bodies and cannot be directly “produced”. Since the magnitude of the gravitational force depends on the mass and distance of the bodies acting on each other, we can make a smaller model of the Earth with the same gravitational effects on its surface ...
Can water somehow be lost to space, i.e. decrease on the Earth?
It certainly can, and in my opinion, it happens to a very limited extent. If we want anything to leave the Earth's gravitational field, we have to give it the so-called 2nd escape velocity (or Ve). Everything we throw/fly slower will come back or will orbit the Earth in an ellipse. The value of this speed is (at the Earth’s surface) 11.2 km/s ...
Why doesn’t the Moon fall to the Earth?
The fact that the Moon orbits the Earth, does not fall on it and does not fly away, and in fact, the fact that it has become our companion, is due to a suitable combination of the speed of the Moon and its distance. According to Newton’s first law, bodies on which no force acts move in uniform rectilinear motion. If a force acts on a body, the body will move with acceleration ...
Can wind turbine rotor tips spin at supersonic speed?
The larger the wind power plant, the faster the ends of its propellers are spinning. Could it be that if the wind farm is very large and the wind is strong, the tips of its propellers will start to sp ...
Small wind turbines can reach 30 to 60 revolutions per minute, but larger ones spin more slowly at a rate of perhaps only ten revolutions per minute. What may look like slow motion from a distance is actually quite fast when you focus on the tips of the propeller blades ...
Could early humans have had a nuclear reactor?
It is said that once upon a time there was a natural reactor in the rocks somewhere. If this is the case, could the first early humans have warmed themselves with it? Couldn't they have baked a mammot ...
A natural reactor really existed. It was "operated" in the Oklo locality in the West African state of Gabon. The uranium ore deposits there at that time contained around three percent of the isotope U235, which is a concentration sufficient for current nuclear reactors ...
What does a heat pump need electricity for?
A heat pump is said to be a miraculous machine that will heat my home from heat collected somewhere outside. But now I found out that it needs electricity to operate ...
A heat pump is actually a bit like a refrigerator. While a fridge takes heat from its interior and heats the room in which it stands, a heat pump takes heat from the external heat reservoir to heat the interior of the house. A suitable reservoir can be the surrounding air, the ground on which the house stands or a water tank ...
How small can a nuclear reactor be?
Nuclear reactors in nuclear power plants are quite large. But how much fissionable uranium do we need, so that a controlled reaction can take place in it and produce heat? Can we build a nuclear react ...
The smallest amount of fissile material in which a fission chain reaction can take place is called the critical amount. Most of the neutrons produced in it during fission continue to participate in fission. This allows the reaction to run continuously. The critical amount depends on the type of fissile material, its concentration and the shape in which it is arranged ...
Can radioactivity be seen?
It is said that radioactivity cannot be seen, heard or felt. But isn't there the possibility that we could see it under certain circumstances? Aren't there any animals, whose senses would allow them t ...
Ionizing radiation is all around us. It arises from the decay of atoms in our surroundings and in our own bodies or it comes to us from space as cosmic radiation. We call materials containing unstable isotopes radioactive, but since everything around us is slightly radioactive, we have not developed senses to detect radioactivity ...
Why do I tan more in winter than in summer?
To be honest, I haven’t experienced this but it’s probably because I don’t sunbathe much. I don’t know if the winter tan is also related to the skiing/mountain activities. If this is indeed the case, I think it has two causes ...
Why can’t you make a fire using a magnifying glass and some “special” flashlight or moonlight?
It would certainly be possible but we would need either a better flashlight or a bigger magnifying glass. About 1,000 W/m2 of energy reaches the Earth from the Sun. If the Moon reflects roughly 20% of the falling sunlight, we would need a 5x better magnifier (i.e. a magnifier with a 5x larger surface, i.e. a 2.3x larger radius) ...
According to what pattern do sunrises, sunsets, moonrises and moonsets change?
The movements of bodies in the central gravitational field are described by Kepler's laws, of which only law 3 has the form of a formula. Isaac Newton used Kepler’s laws to formulate (his) law of gravity ...
Can someone break a glass or any object with their voice (sound made)?
Everything can be broken, the only question is how difficult it will be. It will be simple in theory with a glass but I personally wouldn’t trust the implementation, especially due to the absence of a musical ear?
When we tap the glass, we can hear a sound. The pitch (frequency) of this sound depends on the material and shape of the glass ...
Why can engine performance be determined by “horsepower”? Is it some kind of conversion to real horses? What kind?
Horse power was introduced by James Watt to be able to approximate the power of the steam engine. Simply put, by determining the horsepower of a horse and comparing it to a steam engine, he could say: “My steam engine will replace 10 horses”. This way it was easy for everyone to imagine and was certainly well thought out in terms of marketing ...
Why is the selfie photo rotated horizontally?
All photos are basically rotated, more precisely inverted. This is because the display system of the camera/mobile phone has to create an actual image on the sensor. If we want to use a lens/mirror to create a real image, it will always be inverted. In the same way, the lens in our eye creates an inverted image on the retina and the brain “turns” it around ...
What food is the most radioactive?
I believe that the content of radioactive substances in food depends mainly on where we get the food from. Radioactive materials enter food from its surroundings. Plants and mushrooms get radioactivity from the soil they grow in and animals have radioactive particles in them either from food (plants) or air/water ...
What happens to lightning (energy) when it goes down a lightning rod to the ground?
In general, energy that we can’t use turns into heat and that’s what happens with lightning energy. It is necessary to realize that lightning is actually a slightly stronger example of an electric current (we call it an electric discharge) and therefore the same applies to it as, for example, to an electric kettle, a light bulb or a washing machine ...
Why is the colour of photos of the countryside different in the morning and in the evening (the sun has a similar angle)?
I don’t think that there would always be a difference between the photos in the morning and in the evening, I would rather expect that we can observe something similar from time to time. And I would guess especially in the summer ...
