Velocity of Item Falling Within A Sphere

AI Thread Summary
The discussion centers on calculating the velocity of an object falling within a sphere, specifically a titanium sphere. It highlights that a shell of material, like titanium, exerts no net gravitational attraction on objects inside it. Participants reference the physics problem of a tunnel through a solid sphere, similar to the Earth’s center problem. The gravitational field's variation beneath the sphere's surface is crucial for determining the object's kinetic energy as it falls. Understanding these principles is essential for solving the problem effectively.
PhysicsIsNotMe
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Is there a formula for the velocity of an item falling within a sphere of a specific material, say titanium, This is related to a problem I posted yesterday about Titanium Devouring Aliens.
 
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What does being inside the sphere have to do with anything?

(If you are wondering about the gravitational attraction of the sphere itself, shell of material has NO net gravitational attraction for anything INSIDE the sphere.)
 
:mad: :mad: :mad: :mad: :mad:

at least show some work you might have put into it
 
I think PhysicsIsNotMe is talking about having a tunnel dug through a solid sphere. (Just like the hole to the center of the Earth problem that has been discussed here many times.)

You need to figure out how the gravitation field varies as you go beneath the surface of the sphere. You can then integrate to find the change in gravitational potential energy, from which you can find the KE for an object dropped into that hole as a function of distance fallen.
 

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