Exploring the Earth's Center: Ball Drop Speed vs Distance Plot

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Dropping a ball through a hole drilled straight through the Earth would create a speed versus distance plot resembling a mass-spring system, assuming uniform density and no wind resistance. The ball would accelerate towards the center, overshooting due to inertia before reversing direction. The gravitational force would decrease linearly as the ball approaches the center, leading to a sinusoidal motion. This scenario is often discussed in undergraduate mechanics courses, highlighting fundamental physics concepts. The discussion emphasizes the intriguing dynamics of gravitational forces and motion within a uniform spherical body.
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If I drilled a hole all the way through the earth, and then dropped a ball down one end, what do you think the speed versus distance plot would look like?

I am interested in the centre point of the Earth primarily - instinct tells me it would overshoot by quite a bit, but how far?

assume no wind resistance
 
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Molydood said:
If I drilled a hole all the way through the earth, and then dropped a ball down one end, what do you think the speed versus distance plot would look like?

I am interested in the centre point of the Earth primarily - instinct tells me it would overshoot by quite a bit, but how far?

assume no wind resistance

And if other assumptions to be made include the Earth as a sphere with uniform density, no spinning, etc... then if you solve for the gauss's law equivalent for the gravitational field, you'll get a mass-spring system!

This is a common question in undergraduate mechanics course.

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