if earth is turning on its own axis , then why gravity is the same at poles and equator?

Question

since the centrafugal force at the equator must counteract the gravity to certain amount? or shouldn't it ??

Answer 1

This is actually a very good question. This one actually left me kinda stumped.
My thought on this is that since in relationship to the size of the earth and the rate it spins that centrifugal force doesn't have enough force to make a significant amount of difference. Jupiter, for instance, rotates one time in about eleven hours which is much faster than the earth considering its size. The diameter at the equator of Jupiter is actually greater than the diameter from pole to pole and this is due to centrifugal force. Excellent question. Hope I helped.

Answer 2

"Gravity" (the acceleration towards the centre of Earth) is NOT the same at the pole as it is at the equator. For a 200 pound person, the difference caused by the centrifugal force is a few ounces.

1) The surface at the equator is a bit further from Earth's centre than the surface at the pole (difference is 21.4 km = almost 13.4 mi). Because gravity varies as the square of the distance, the difference is almost 1 lb 5 ounces for a 200 pound person.

2) the centrifugal force is nil at the pole and a few ounces at the equator. It can be measured with very accurate lab equipment, but it is a lot less than the difference due to the bigger equatorial radius.

Here, "gravity" is used in its old Newtonian sense of "Earth's attraction"
That is how Newton used the word. He talked of gravity for the acceleration that resulted from the force that attracted objects towards Earth's centre, and of another force that kept objects in orbit around the Sun. What he showed is that the force was calculated in the same manner. Its value changed depending where you were (or what planet's orbit you were considering).

Answer 3

It's true that the poles or areas near the poles move slower that the equator. That's why they try to launch satellites from as close to the equator as possible. The faster moving area gives the rocket an edge in speed or in most cases payload over a rocket launch from a more northerly location The Earth's rotation has no effect on gravity. Centrifugal force can be used as artificial gravity on theoretical spinning space station.

Answer 4

Gravity is not the same at the poles and the equator.
Gravity is purely the result of mass and the distance you are from the centre of mass.

The equator bulges out a little (making the Earth oblate, not completely spherical) and as such when you stand on the equator you're about 22 km farther from the centre of the Earth than at the poles. And yes, there is a tiny bit of compensation by centrifugal force at the equator, but its insignifcant. This effect results in the gravitational force of 9.789 ms^2 at the equator and 9.832 ms^2 at the poles.

Answer 5

Technically, the Earth’s gravity is slightly less at the equator than the poles. Not however because of the centrifugal force trying to throw you off of the Earth. (That would actually be two forces acting on a body, not a reduction of the gravity) But because of the centrifugal force over time has caused the Earth to flatten slightly (about 24km) so that standing at the equator moves you farther from the center of the earth thus it's effect is reduced by distance.

Answer 6

Interesting thought but based on a wrong premise. The force certainly does counteract gravity. Unfortunately the force is so small it is hardly worth bothering about. However, people who launch spacecraft get a head start firing as close to the equator as they can.

The actual value for observed g at the poles is 9.83 to 9.78 at the equator. It is not simply rotational force. This is also due to the bulge of the earth at the equator making gravity weaker.

Answer 7

The shift wouldnt change anything. The axis would just change the environment, but not astrology. The north and south pole of the earth would change, but its sync rotation would be the same. As long as the orbit of the earth dosent change from the sun, our signs would still be the same. Astrology is measure by earth + orbit location = constallation sun. Etc etc. It is measured by the orbits, not axis

Answer 8

Actually the gravity isn't the same. You wiegh 1/4 of a kilogram less at the equator then you do at the poles.

Answer 9

Gravity is not the same at the poles and the equator:

The standard value for Earth's gravity at sea level is
9.80665 m·s^−2
The mean value at the equator is 9.789 m·s^−2
The mean value at the poles is 9.832 m·s^−2

The standard weight of a mass of 1 lb is 1.000 lb

Weight at the equator = 1lb / 9.80665 m·s^−2 * 9.789 m·s^−2
= 0.9982 lbs

Weight at the poles = 1lb / 9.80665 m·s^−2 * 9.832 m·s^−2
= 1.00259 lbs

Answer 10

well there is a small diffrnece actualy but it is actualy because the earth is not a perfect sphere and that it buldges at the equator.