Ionic Bond – NaCl
Ion Atoms are made up of an atomic nucleus and electrons. Electrons far from the atomic nucleus may easily fall off, or electrons from outside may enter. If a neutral atom loses an electron, the amount … more
Michelson Interferometer
Michelson interferometer The Michelson interferometer was invented by the American physicist Michelson. Although it has a simple structure, it can measure very small distance differences, such as the size of an atomic nucleus. The Michelson interferometer … more
Twin Paradox
Twin Paradox Twin paradox started as a contradiction in ‘time delay’ in Special relativity. The Twin Paradox goes something like this: (Contents vary depending on the media.) One of the twins stays on Earth, and the … more
Minkowski Spacetime
Minkowski Spacetime Minkowski spacetime (or Minkowski space) is a coordinate system devised by German mathematician Minkowski. The peculiar thing is that the coordinate system contains space and time. Minkowski spacetime uses matrices to express a four-dimensional … more
Special Relativity: Length Contraction
CAUTION: Read the following instructions to the end to get the result that the moving object appears to be constricted in length. (It is difficult to explain ‘Special Relativity’ only with the above simulation.) The meanings … more
Special Relativity: Time Dilation
The meanings of the symbols used in this simulation are as follows. L = Distance that light travels in a stationary state, (=ct｡) c = Speed of light (≒ 299,792,458 m/s) t｡ = The transit time … more
Why do we always have crystal ball covered?
Why do we always have crystal ball covered? While surfing the web, I came across a fascinating article on Twitter. It sounds like a fun topic, so we decided to simulate the refraction of all light … more
‘Moment of inertia’ of various shapes
You can click various shapes on the left and right sides of the screen. What are the characteristics of a shape with a large moment of inertia? What are the characteristics of a shape with a … more
Evolution of the eye
Flagellate Hundreds of millions of years ago, light-sensing organelles arose inside the monad. Creatures with ‘photoreceptors’ are able to distinguish day and night and can also avoid harmful ultraviolet light. Flatworm And these photoreceptors have evolved … more
Correction of Near-sightedness & Far-sightedness
Focusing The light started from the object must have arrived exactly at one point on the retina to see things in detail. On the other hand, if the light from one point of the object is … more
Equilibrium Constants
2●\(\rightleftharpoons\)● Chemical equilibrium In a chemical reaction, chemical equilibrium is the state in which both reactants and products are present in concentrations that have no further tendency to change with time. In an equilibrium state at … more
Tuning Fork and Sound Wave
Tuning fork The tuning fork has a structure that combines the ends of two sticks. When the tuning fork is vibrated, the tuning fork repeatedly approaches and then moves away from each other. The vibration mechanism … more