Transportation changed how humans interacted and lived thanks to radical innovations such as the automobile, electric rail cars, airplanes and internal combustion engines, according to the Smithsonian. Suburbs grew, people moved across the world faster and humans became more mobile because of transportation technology.Know More
By 1920, Americans owned eight million vehicles. In 1950, that number was nearly 50 million. In 2000, there were 220 million cars on American roads, more than the number of people 18 or older. In the last 100 years, cars became safer and roads turned from dirt to asphalt or concrete.
Vessels on the ocean got bigger and goods moved faster. Engines ran on steam and coal but then switched to diesel power. Hulls were made of steel instead of wood, which led to increases in ship size. The Panama Canal, finished in 1914, cut down shipping times between the Atlantic and Pacific Oceans.
Commercial airlines expanded rapidly in the 1960s when safety improved and jet engines became the norm. Millions of new passengers were added during this expansion of air travel. By 2000, two million people traveled by air on a daily basis in the United States. Until airplanes took over intercontinental travel in the 1950s, ocean-faring vessels dominated travel between countries.Learn more about Industrial Revolution
Airplanes have changed in their size, engine systems, control systems, construction, and range and payload capabilities since the first powered aircraft took to the air in the early 20th century. Modern passenger airplanes are larger, faster, more powerful and also more fuel-efficient as compared to early aircraft.Full Answer >
Crime statistics by race have not significantly changed in the last century. African Americans and Latinos, despite making up approximately 30 percent of the total general population, account for approximately 60 percent of the prison population in the United States. The most recent decade has seen some promising changes, though.Full Answer >
The transit of Venus happens every 100 years. The last one was in June 2012, and the next one occurs in 2117. This happens as Venus directly passes between the Earth and the Sun. This once-in-a-lifetime astronomical alignment has been witnessed eight times since the telescope was invented. These eye-witness-accounts occurred in 1631, 1639, 1761, 1769, 1874, 1882 and 2004, and the last was in June 2012.Full Answer >
Propane usage depends on the nature of use, such as appliances, furnaces and fireplaces, as well as the climate. Each gallon of propane provides 91,547 British thermal units, or BTUs. Appliances can vary a great deal from about 25,000 BTUs per hour to more than 400,000 BTU per hour.Full Answer >