## Where did the pendulum’s energy go? (The second law of thermodynamics and irreversible phenomena)

Where did the pendulum’s energy go? A pendulum that vibrates in the air continues to collide with air molecules in the process of vibrating. Air molecules get their energy from the pendulum. In this process, Air molecules increase their speed. … more

## Force to move the pendulum

Tension by gravity In physics, tension is the force on a string connecting two objects. Generally, the tension is calculated from both ends toward the center. When the length of the pendulum is $$l$$, let’s consider the pendulum raised and … more

## Spring pendulum(horizontal)

This simulation ignored the effects of friction. Simple harmonic oscillation In everyday life, we see a lot of movements that repeated the same oscillation. Like below, shaky or suspended objects are doing this oscillation. Clock pendulum An object suspended in … more

## Foucault Pendulum (WebGL)

Foucault’s pendulum is a device invented by French scientist Leon Foucault to prove the Earth’s rotation in 1851. The fact that the Earth rotates has been known for a long time, but it is the first example that proves it … more

## The principle of riding a swing

Kids have the know-how, but they can’t tell the principal. “How can you go so high?” Some principles are difficult to describe in words in the world, even if everyone knows. I think one of them is how to ride … more

## Period of Physical Pendulum

A pendulum that vibrates is one of a ‘simple pendulum’ or ‘physical pendulum.’ A simple pendulum is a case in which an object’s angular motion can be ignored, such as a small object suspended from a string. Most pendulums are … more

## Spring Pendulum(Vertical)

This simulation ignored the effects of friction. Simple harmonic oscillation In everyday life, we see a lot of movements that repeated the same oscillation. Like below, shaky or suspended objects are doing this oscillation. Clock pendulum An object suspended in … more