Surely you’ve thought many times, while stuck in traffic, squeezed in a crowded bus, or wracked by turbulence on a plane, how great it would be to be able to get from place to place without the hassle of travel. If you could walk through a magic door and find yourself in the Seychelles or Paris. If there was a teleport that could take you anywhere you wanted in the blink of an eye ...

The film projector uses three colours of light — blue, green and red. By mixing them, all other colours are created. To watch a movie, whether it’s projected on a wall at home or on a big screen at the cinema, you need a movie projector that will project beams with information about the image ...

The term “black hole” was first used in 1967 by Frank Wheeler to describe a cosmic body, which until then had been called a “black star” or a “gravitationally completely collapsed body”. It is a bizarre object that is so massive and dense that not even light can escape from it. Its existence results from Einstein's theories ...

Boiling is a special case of evaporation — its peculiarity is that it occurs at a specific temperature (the boiling point) and at this temperature, evaporation takes place throughout the entire volume of water (which are the mentioned bubbles) and not just on its surface. The boiling point of water depends on the pressure above the surface of the liquid ...

Because electricity and magnetism are closely related (they are actually different manifestations of the same phenomenon), the magnetic properties of substances are related to electrons. Each electron is a (very small) magnet. If we manage to arrange these magnets in the same way, the body in which these electrons are will have magnetic properties ...

Temperature does have an effect on the speed of particle movement, but this effect is minimal compared to the influence of nuclear forces and therefore, (except under extreme conditions) the half-life of nuclei at different temperatures does not change ...

First, I need to clarify the difference between calories and units of energy, which are joules. Calories were previously used to determine the value of heat and it has been shown (for example in the First Law of Thermodynamics) that heat is one of the forms of energy. The term calorie is still used (especially in food and metabolism), but it is merely a converted value of energy. One calorie is 4 ...

I think that this question cannot be answered simply and briefly and I will rather try to explain why it cannot be answered. Perhaps it will then be clearer why the answer is fundamentally impossible. When producing electricity, we have to consider many completely different criteria, and only then can we address the specific fuel ...

Of the four known types of forces, only two interact between an electron and a proton — gravitational and electrostatic. Both have a similar method of calculation, with gravitational force depending on the mass of the interacting bodies and electrostatic force depending on their charge ...

The size of an atom is in the tenths of nanometres (0.0000000001 m), and the nucleus is even 100,000 times smaller. From this ratio and the fact that the mass of protons is approximately 2,000 times greater than the mass of electrons, among other things, it follows that 99.999% of an atom is actually empty space ...

In my opinion, the speed of an electron's movement in the electron cloud cannot be determined by direct measurement (electrons are too small for that), but we can use an analogy from astronomy — for example, the Moon orbits the Earth at a speed such that the magnitude of the centrifugal force is equal to the gravitational force ...

Just like with everything in our surroundings, it is necessary to determine under what conditions we want to measure the temperature in. For example, water can be at 4 °C in the refrigerator, 95 °C in an electric kettle, and around 300 °C in a power plant (typically nuclear) ...

So far, outer space in the solar system is a peaceful place where no one is shooting at anyone, but we can feel free to entertain hypotheticals about what if we needed to. Maybe that astronaut doesn’t want to shoot another astronaut, but a creepy alien monster ...

Freezing is a process in which a liquid state changes to a solid state. Solid crystals begin to grow in the liquid and more and more molecules of the freezing liquid are added to them. Eventually, one solid block is formed. In water, we call it ice. In order to freeze, the molecules need to get rid of the energy that prevents them from getting a firm grip in the crystal bonds ...

When we heat water, it starts to evaporate. At first, it evaporates only from the surface, and when it reaches the boiling point, it evaporates from its entire volume. The water changes from a liquid to the gaseous state called steam. At some point, an equilibrium is established. As many molecules evaporate from the water as condense back into it. The steam thus obtained is called saturated steam ...

Human beings have always longed to be invisible. Fables and myths are full of potions, incantations and cloaks of invisibility. H. G. Wells attempted to grasp the idea of invisibility a little more scientifically in his novel The Invisible Man. In it, the hero invents a substance that makes all the cells of his body transparent ...

The ability of dinosaurs to construct radiation detectors, take measurements, and record the results has not yet been proven, and it is quite likely that they did not actually do any such thing. Yet we know the half-lives of elements that are longer than the time that dinosaurs ruled the Earth. In order to explain how this is possible, it is first necessary to clarify what the half-life is ...

Photons are particles with zero rest mass moving in a vacuum at the speed of light. As bosons, they are not constrained by the Pauli Exclusion Principle and can pass through each other or occupy the same quantum state ...

The nucleus of each atom is made up of protons with the addition of more or less neutrons. It is thus theoretically possible for an element to exist with any number of protons in its nucleus. Perhaps a thousand or a million. But protons, as charged particles, repel each other, and the more there are in the nucleus, the harder it is to keep the nucleus together ...

The fission chain reaction in a nuclear reactor takes place when a neutron flies to a uranium-235 atom and collides with it, splitting the nucleus into two or three fragments. Several neutrons fly out of the whole process, slow down appropriately, collide with other uranium atoms, and so on. Each fission of uranium generates neutrons, which cause other uranium nuclei to fission ...