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The Physics Behind Running (2)

Whenever you are running, the highest level of potential energy is at the peak height both, the knee and/or foot reaches. This is because the distance between your foot, and/or knee, and the ground, h, directly affects the potential energy output. It can be proven by the equation:

Potential Energy= (mass)(gravity)(height)

In this case, the values of mass and gravity do not change. However, the distance, or height, between both, your foot and/or knee, and the ground varies as you run. Therefore, as your height increases, potential energy increases.

(V)

The Wheel

The oldest recorded wheel was a wooden model built by the Slovenians and dated around the year 3,200 B.C. It was built of ash and oak. At this time the axel was also built. This device was indented to rotate with the wheel so that it could be used to mount to a structure, such as a pushcart, in order to provide transportation.

Source: The Slovenia Times 2017

Thomas Jefferson and the Metric System

The efforts to introduce a system of measurements based on 10 date back to Thomas Jefferson. It was not exactly the metric system as we know today, but an original system of measures based on 10.

Here is an example of those original units:

Length

"Let the foot be divided into 10 inches; the inch into 10 lines; the line into 10 points. Let 10 feet make a decad; 10 decads one rood; 10 roods a furlong; 10 furlongs a mile"

Weight

"Let the ounce be divided into 10 double scruples, the double scruple into 10 carats; the carat into 10 minims or demi-grains, the minim into 10 mites. Let 10 ounces make a pound; 10 pounds a stone..."

(Source: Plan for Establishing Uniformity in the Coinage, Weights, and Measures of the United States Communicated to the House of Representatives, July 13, 1790)

If that does not sound familiar, that's OK. Despite the fact that the idea was supported by people like George Washington and Alexander Hamilton, the system proposed by Jefferson was never accepted.

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Just for the record... Where are we with the units today?