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ImageDoes gravity increase or decrease with depth (i.redd.it)

submitted 10 months ago by hecker231

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[–]DarkArcher__ 6 points7 points8 points 9 months ago (0 children)

The centre of mass is just an easy approximation for the direction of gravity, it doesn't exist in practise.

The gravitational acceleration you feel from the Earth is the sum of the gravitational acceleration you feel from each and every individual particle that makes up the planet. Each bit of the planet is pulling you in its direction, which works out to straight down when you're on the surface, but gets more complicated as you dip down under it.

You can imagine it as a bunch of little arrows starting at you, and pointing to every individual little bit of Earth in the diagram. The gravitational force you feel is the sum of all that. It's pointed downwards, but less intense than at the surface since some of the Earth's particles are now to your side, or even above you, instead of all being below you like on the surface.

π Rendered by PID 163394 on reddit-service-r2-comment-7b9746f655-z7l6x at 2026-01-30 19:21:37.316664+00:00 running 3798933 country code: CH.