What causes the change in velocity from pole to equator on Earth?

[papernuke]

Assume there's a person standing at the pole of the earth. When the Earth rotates, he/she has no tangential velocity because the person is at the pole.
Now if the person were to take a trip by plane and land at the equator, the person would now have a fairly large velocity because the equator's tangential velocity is quite high.
What provides the acceleration that that changes the person's velocity from zero at the pole to 1,670 kph at the equator?


source for 1,670: http://geography.about.com/library/faq/blqzEarth'spin.htm

 

[Simon Bridge]

Why the Earth does - and the engines in the means of transportation.

Consider, you are in free fall above an airless spherical World composed entirely of ice and you are wearing ice-skates.
The world is turning below you. The ground gets closer - your feet touch the ground - the world keeps turning under you.

From your POV, you are now skating very fast across the surface.
Turn your skates and you can slide to a "stop" - now you are going at the same speed as the surface under you ... where did the acceleration come from?

 

[Nugatory]

Assume there's a person standing at the pole of the earth. When the Earth rotates, he/she has no tangential velocity because the person is at the pole.
Now if the person were to take a trip by plane and land at the equator, the person would now have a fairly large velocity because the equator's tangential velocity is quite high.
What provides the acceleration that that changes the person's velocity from zero at the pole to 1,670 kph at the equator?source for 1,670: http://geography.about.com/library/faq/blqzEarth'spin.htm

If we ignore variation from the local wind and weather on the surface of the earth, the air at the equator is moving at 1670 kph relative to the air at the north pole. So as the airplane flies southwards, it experiences a sidewind blowing from the west that accelerates it in an eastwards direction.

If you were walking south from the north pole, with every single step you'd be putting your foot down on a patch of Earth that is moving ever so slightly faster to the east than where your foot had been. It's not much at each step, but it's enough to add up to 1670 kph over the 20,000,000 or so steps between pole and equator.

You might want to google for "Coriolis force".

 

[papernuke]

Thank you both for the explanations!
I understand it now

 

[PJC01]

The change in velocity from pole to equator on Earth is caused by the Earth's rotation and its shape. The Earth is not a perfect sphere, but rather an oblate spheroid, meaning it bulges at the equator and is flattened at the poles. This shape results in a difference in the distance from the center of the Earth to the surface at the poles and the equator.

As the Earth rotates, objects on the surface, including the person standing at the pole, are moving with the Earth's rotation at a constant angular velocity. However, due to the Earth's shape, the person at the pole is actually traveling a shorter distance than the person at the equator over the same amount of time. This results in a difference in tangential velocity, with the person at the equator having a higher tangential velocity than the person at the pole.

When the person takes a trip from the pole to the equator, they are essentially traveling from a smaller circle to a larger circle, which means they are covering a greater distance in the same amount of time. This results in an increase in tangential velocity, and since velocity is a vector quantity, this change in direction and magnitude of velocity is considered acceleration.

Therefore, the acceleration that changes the person's velocity from zero at the pole to 1,670 kph at the equator is the result of the Earth's rotation and its shape. This phenomenon is known as the Coriolis effect and is responsible for many of the global weather patterns and ocean currents that we observe on Earth.