Well-connected transportation

Author: Dong Ge
Publisher:
Publish Date: 2003-01-01
Features: "Clothing, Food, Shelter, and Travel" are indispensable to humans. In the early stages of human society, humans relied on their own legs to move around in pursuit of migrating prey or to escape the harsh cold of winter. Later, out of the need to trade with other tribes, races, civilizations, and people, the scope of human activities expanded. The motivation for "travel" changed, leading to the continuous evolution of travel methods. Initially, humans were limited to traveling on land. Later, people could travel on water, underwater, and in the air. Today, we can even travel in space. In today's society, the motivations for "travel" are even more diverse: people go to work, interact with others, engage in entertainment, and travel to faraway places—these are all motivations for "travel." Humans have also ventured into previously unknown realms. In the deep sea, people search for treasures from sunken ships or explore new resources; in the sky and space, people observe and gain in-depth understanding of the Earth, or, to put it simply, people simply satisfy their desire to explore the distant universe. To achieve the above purposes, humans have invented means of transportation such as cars, submarines, and space shuttles. Why is a submarine spherical in shape? How does a space shuttle return to Earth? The answers can be found in the experiments in this book.