## Brownian motion

Brownian movement Botanist Robert Brown, while observing pollen on the water’s surface, He noticed that the pollen was constantly moving in random directions. At that time (1827), Brown believed that these movements were driven by special powers as a living...

## Sum of Exterior Angle

Polygonal Exterior Angle Imagine drawing a polygon with a pencil. While drawing a straight line with a pencil, We change the direction at the vertex. The size of the angle changing direction at the vertex becomes ‘exterior angle.’ If you...

## Lorentzs Force

Direction of the Lorentz force Conductors in which current flows in a magnetic field are forced to move. The direction of this force is perpendicular to the current and the magnetic field, respectively. More precisely, we can find out below....

## Psychrometer(hygrometer)

hygrometer It is a simple device that allows you to determine the humidity by measuring the difference in how much water evaporates. Compared to a simple structure, humidity can be measured relatively accurately. Before electronic hygrometers became popular, psychrometers were...

## Absorption and Emission of Light

The energy level of the atom Atoms are made up of an atomic nucleus and electrons that revolve around the nucleus. In Bohr’s atomic model, electrons can change their position by receiving energy (mainly light energy). But what’s unique is...

## Principle of least time (Fermat’s principle)

Why does a slightly curved path take less time than a straight path? Ants can move faster on flat stones than on rugged grass. Therefore, travel time is the shortest on slightly curved paths. This principle of the least time...

Three elements of force When a force acts on an object, the object’s motion varies depending on the Three elements of force. That is the magnitude, direction, and point of action. Therefore, when displaying a force, you must indicate the...

## Circumference of a Circle

How to find out the circumference of a circle Let’s draw a regular polygon (inscribed polygon and circumscribed polygon) surrounding a circle. The perimeter of an inscribed polygon is less than the perimeter of the circle, and the perimeter of...

## Pythagorean Theorem

Pythagorean theorem Assuming that the three sides of a right triangle are a, b, c, and the longest side is c, the Pythagorean theorem is that the equation a²+b²=c² is always true. The equation a²+b²=c² represents three squares created using...

## Flame Test

* This simulation take the spectral data from NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY. When heat is applied to the atoms, some electrons can have high energy levels and fall to the lower levels. Some electrons emit as much energy...

## Electromagnetic Waves

What is light? A form of energy that brightly illuminates the world we live in is called light. Various electromagnetic waves, including visible light, are emitted from hot objects or objects with energy. Visible light is the part of the...

## Diurnal Motion of Sun

Diurnal Motion Fix the camera towards Polaris at night, shoot for a few hours, and you’ll see the stars move in a circle around Polaris. This movement of the stars in a circle once a day is called a diurnal...