Free Travel due to Earth’s rotation
Earth's Rotation - Basics
Do you believe that our earth is rotating about its axis? If Yes, can we make a free trip from one place to another on earth using this phenomenon? We can observe that the sun, the planets and the other celestial bodies move around us from east to west. It is because either the bodies actually move around the earth in the east-west direction or the earth rotates from west to east. As the earth is very small compared to other bodies, the earth cannot have enough force to make the other bodies to move around it. Therefore the only possibility is that the earth rotates from west to east.
The day and night phenomenon occurs due to the fact that the earth rotates. Suppose you want to travel from India to an African country, say Egypt. Hire an air balloon and get into it. Float it to a reasonable height. Wait for few hours on the sky. Let the earth rotate from west to east. Now you can land on the soil of Egypt. Do you believe this will work? Certainly not. Because the earth rotates together with its atmosphere, we are able to live on earth stably. Otherwise we will be thrown out of the earth.
Another interesting reason for the rotation of earth is as follows. Earth is not spherical in shape, but an oblate spheroid. It has its polar regions flattened and the equatorial regions bulged. The polar radius (3950 miles/6357 km) is shorter than the equatorial radius (3963 miles/6378 km). When earth was born it was in fluid state. By the theory of Fluid Mechanics, the end portions of a rotating fluid are flattened and the central portions bulged. Therefore the flattening at the poles and bulging at the equator of the earth must be due to the fact that the earth was rotating from the beginning of its formation. Therefore the earth was rotating, is rotating and will be rotating forever.
A person standing on the equator rotates at approximately 1038 miles per hour (1670 km/h). Does a person standing exactly on the North Pole withstand this speed? Do you think that he will be rotated at an extreme speed? But it is not so!
For other places with latitudes...
10° - 1022 mph (1644 km/h)
20° - 975 mph (1569 km/h)
30° - 899 mph (1446 km/h)
40° - 795 mph (1280 km/h)
50° - 667 mph (1073 km/h)
60° - 519 mph (835 km/h)
70° - 355 mph (571 km/h)
80° - 180 mph (290 km/h)
You can understand that when the latitude of a place increases, the speed of earth’s rotation decreases. (You recall the formula: Velocity = radius X angular speed) Therefore, at the North Pole (90 degrees north) and South Pole (90 degrees south), the speed of earth is almost zero since the person standing there rotates once in 24 hours, a very, very slow speed. Earth is also speeding at about 66,660 miles per hour (107280 km/h) in its revolution around the sun. Is it a uniform speed? No. We will see in the next hub.