# Playground of the Mind with Dan

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## The history of the light bulb

When people think of the light bulb, they just think of Edison. That is not the case. in 1802, Humphry Davy created the first electric light. He heated carbon with a battery until it started to glow. This was known as the electric arc lamp. This invention didn't work because it didn't last very long and was just too bright for an practical uses. In 1840, Warren de la Rue enclosed a coiled platinum filament in a vacuum tube and passed an electric current through it. The design was based on

## Lift Forces

A fluid that flows past a surface of a body exerts a force on it. Lift is the perpendicular component to the oncoming flow, of this force. It is the opposite of a drag force. Aerodynamic lift is different from other kinds of lift. Aerodynamic lift requires relative motion of the fluid. It usually refers to when an object is completely immersed in a fluid. Lift is what makes it possible for a plane to fly. Lift is also used in Frisbees. As man takes to the sky, we owe much to the power of l

## Resonance

Many cultures and spiritual factions speak of the importance of frequencies and vibrations. many cultures believe it plays an important role in nature. Certain frequencies create geometric shapes as the frequency increases, the patterns get more complex.

## Water and Sound

The video below shows a very cool experiment. It shows how the flow of water changes when a vibration is applied. water reacts very strangely when it is vibrated. enjoy

## 2D Reubans tube.

In physics you learn about waves. However, many people don't realize that waves are every where. A rubens tube is a tube with natural gas pumped through it with holes in the top. when a steady vibration is used on the tube, a standing wave is formed. It has nodes and anti nodes like any wave. When you put a lot of vibrations through, like say music, the effect is very cool. Most rubens tubes are just a linear single tube, in this video however, it goes into 2 dimensions the resul