Gravity increases in strength the closer you get to Earth's core
the verdict
REFUTED
the evidence says no
refutedsupported
the weight of evidence
0 sources for · 1 against
AS REPORTEDno primary record reached; this is what the reporting says
Retrieved physics explanations refute the idea that gravity uniformly increases in strength closer to Earth's core, noting that gravitational acceleration actually decreases through much of the Earth's interior depending on mass distribution.
# Why does gravity decrease as we go down into the Earth?
Tags: newtonian-gravity, earth, planets
- Score: 2
- Views: 82059
- Answers: 2
- Answered: yes
- Asked by: Aman Singh (53 rep)
- Asked: 2014-02-14
- Edited: 2018-08-25
- Site: physics
- Closed: closed
## Question
We all know that gravity decreases as the distance between the two increases. Hence
$$ F = G \frac{Mm}{r^2}. $$
Hence the acceleration due to gravity
$$ g =\frac{F}{m}= G \frac{M}{r^2} $$
increases as $r$ decreases. Then why does it decrease as we go deep into the earth?
## Answers
### Answer by joshphysics (score: 8 [ACCEPTED])
It's actually not entirely true that the strength of the Earth's gravitational field decreases as a function of depth. It is true for certain regions in the Earth, but it's untrue for others because of the non-trivial dependence of the Earth's density on depth.
To see what's going on, assume that the Earth is a sphere whose density is spherically symmetric.
Now consider a mass $m$ at some radius $r$ from the center of the Earth. Using Newton's Law of Gravitation, one can show that that given the spherical symmetry, the gravitational attraction on $m$ of all mass with radii grea