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This Hydroelectric Dam Is So Large It Slows The Rotation of The Earth
People affect the Earth in small and large ways
The Three Gorges Dam in China is a massive construct that spans the Yangtze River. The Yangtze is the longest river in Asia. The flow of the river is so powerful that the Three Gorges Dam is the largest hydroelectric station in the world by power produced. The Three Gorges Dam is impressive for a host of reasons, but one reason is especially impressive.
The Three Gorges Dam is truly massive. It is hundreds of feet tall and over a mile long. It has 34 massive hydroelectric turbines that produce thousands of megawatts of power. The reservoir measures nearly 500 square miles in size and can hold 31,900,000 acre⋅ft of river water.
All of these metrics are highly impressive, and the dam is truly a feat of modern engineering. But it also has another impressive metric. The Three Gorges Dam is so large and holds back so much water that it actually slows down the rotation of the Earth.
Moment of Inertia
Scientists have measured how the Three Gorges Dam has slowed down the Earth thanks to some very complicated physics blown up to a massive scale. The calculations revolve around the Earth’s moment of inertia. The moment of inertia is a way to measure how a spinning object is resisting angular acceleration. The distribution of weight on a spinning object can change the moment of inertia and, therefore, the speed of the object’s spin.
The way that the dam slows down the Earth’s rotation is because of the amount of water that pools behind it. As the massive reservoir fills behind the dam, it collects a large amount of water from the Yangtze River. Before, this water flowed at a consistent rate over a defined area for millions of years. Now, the water is halted, and it gathers in a manmade reservoir as it waits its turn to flow through the dam.
According to Business Insider, the collective weight of the water in the Three Gorges Dam’s reservoir is 42 billion tons. That amount of weight accumulating in a small and…
