Does centrifugal force affect weight at different latitudes on Earth?

[John E4-D5]

As a result of various searches on the Net, I have ended up here on this fantastic site. Specifically, it was an old 2008 thread in which was closed, so in order for me to expand on such discussion I've decided to make my own thread; by which I will go a slightly different direction with.

Gravity pulls everything towards the center of the earth, and centrifugal force slightly lessens the effect of gravity's pull. Due to Earth's spin, of course.

Now, at the equator the Earth spins 1500 - 1700 mph. I'm not sure what the specific speed is because everyone uses a different number. But that is besides the point.

Here's my thought experiment for you: If I fly to the equator, and weigh myself at 160 lbs, and then I go to the North Pole, will I weigh more or less than 160 lbs.? If so, by how much?

The circumference of the Earth at the equator is much more than the circumference of the Earth close to the North pole, which would mean that the effects of the centrifugal force would be less, therefore I should weigh more right?

Would this be a reasonable experiment to do, or has it already been done?

Very much looking forward to your replies and insights! Thank you!

 

[russ_watters]

As a result of various searches on the Net, I have ended up here on this fantastic site.

Welcome to PF!

Gravity pulls everything towards the center of the earth, and centrifugal force slightly lessens the effect of gravity's pull. Due to Earth's spin, of course.

Yes.

Now, at the equator the Earth spins 1500 - 1700 mph. I'm not sure what the specific speed is because everyone uses a different number.

Can't you do the calculation yourself? Those values actually aren't all that close.

Here's my thought experiment for you: If I fly to the equator, and weigh myself at 160 lbs, and then I go to the North Pole, will I weigh more or less than 160 lbs.? If so, by how much?

Would this be a reasonable experiment to do, or has it already been done?

NASA has satellites that map the Earth's gravitational field in exquisite detail, being able to detect the differences caused by mountain ranges, oceans and the varying thickness of the crust. Here's the amount of variation:

Effective gravity on the Earth's surface varies by around 0.7%, from 9.7639 m/s2 on the Nevado Huascarán mountain in Peru to 9.8337 m/s2 at the surface of the Arctic Ocean.[4] In large cities, it ranges from 9.766 in Kuala Lumpur, Mexico City, and Singapore to 9.825 in Oslo and Helsinki...

In combination, the equatorial bulge and the effects of the surface centrifugal force due to rotation mean that sea-level effective gravity increases from about 9.780 m/s2 at the Equator to about 9.832 m/s2 at the poles, so an object will weigh about 0.5% more at the poles than at the Equator.

https://en.wikipedia.org/wiki/Gravity_of_Earth#Variation_in_gravity_and_apparent_gravity

Note that in addition to the centrifugal force, there is also the issue that when on the pole, you are closer to the Earth's center.

 

[A.T.]

NASA has satellites that map the Earth's gravitational field in exquisite detail, being able to detect the differences caused by mountain ranges, oceans and the varying thickness of the crust.

It should be noted, that those satellites do not detect the differences due to centrifugal effects.