# Tag Info

Accepted

### Can Newton's gravity equation explain why black holes are so strong?

No you can't and the behaviour of bodies with mass and of light is completely different near a compact, massive object if you use Newtonian physics rather than General Relativity. In no particular ...
• 114k
Accepted

### Intuition about why gravity is inversely proportional to exactly square of distance between objects

Imagine "gravity" spreading out in a sphere, like light from a bulb. For each doubling of the distance, the sphere has four times the area. The surface area of the sphere is proportional to ...
• 87.6k

### Can Newton's gravity equation explain why black holes are so strong?

I am not an expert in physics and the explanation of the others is excellent. However, I noticed a flaw in your reasoning which they did not address. You have written: Considering the Newton's Law of ...
• 241
Accepted

### Gravitational acceleration inside a planet

You can use Gauss's law for gravitation to work out the gravity as a function of (interior) radius. $$\oint \vec{g} \cdot d\vec{A} = -4\pi G \int \rho\ dV\ .$$ What this means is that the flux of ...
• 114k
Accepted

### Gravitational lensing in Newtonian physics

A photon is an entity defined in the context of a relativistic field theory, and so it doesn't really make sense to talk about the Newtonian bending of a photon. Necessarily, we need to substitute an ...
• 7,674
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• 33.7k
Accepted

### Why can't gravity repel things?

Apart from the field-theoretical standpoint presented by Stan, one can repel objects in a sense, when taking orbital mechanics into account. The slingshot maneuver extracts angular momentum and ...

### Intuition about why gravity is inversely proportional to exactly square of distance between objects

The validation is the same as the validation of any astronomical theory: it fits the data. Newton's law of gravitation was formed empirically, by observing the motion of the planets. In particular, ...
• 273

### At what distance does MOND Modified Newtonian Dynamics take effect?

There is no line at which things transition from Newtonian dynamics to MOND, it's more of a gradual continuous transition depending on the nature of the interpolating function $\mu(x)$: From Wikipedia ...
• 1,680

### Gravitational attraction of Sun on distant object

James K gave a good answer to this, but I just want to add that if the Sun was unmoving relative to the center of the Milky-way, it would fall towards the center along with your object. The sun ...
• 22.9k
Accepted

### Precision of geocentric gravitational constant

Ignoring details such as the oblateness of the Earth, atmospheric drag, third body influences such as the Moon and the Sun, relativity, ..., the period of a satellite of negligible mass (even the ...
• 27.1k
Accepted

### Gravitation - Pulling or Pushing force?

In general relativity, gravity neither pushes nor pulls. To explain why ball travels in an arc you note the start and end points of the throw in 4d space time (3 space co-ordinates and 1 time ...
• 87.6k

### Gravitation - Pulling or Pushing force?

I'm guessing that this misunderstanding is a result of the oft-used rubber sheet analogy. The rubber sheet analogy says that, according to general relativity, mass curves space-time like a heavy ...
• 33.7k
Accepted

### How can I predict space directions?

If you project the orbits onto a plane, for example the plane of the ecliptic, the projections will cross. But that's only because you're looking at a 3D problem in 2D. If you look at the orbits in 3D,...
• 634

### Why does a particle feel no force at radii greater than itself?

"in a spherically symmetric distribution of matter, a particle feels no force at all from the material at greater radii, and the material at smaller radii gives exactly the force which one would get ...
• 1,743

Only top scored, non community-wiki answers of a minimum length are eligible