All Questions
Tagged with newtonian-gravity planets
311
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Dynamic equilibrium of planets
We can describe statical equilibrium ( forces, moments ) in a cuboid $$ \Sigma F_x=0,\Sigma F_y=0,\Sigma F_z=0~$$ In dynamics can we describe similar dynamic equilibrium within an inertial ...
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What does Newton's Theorem XXXIII in his book "Principia" mean?
If to the several points of a given sphere there tend equal centripetal forces decreasing in a duplicate ratio of the distances from the points; I say, that a corpuscle placed within the sphere is ...
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How would the volume of a drop of water (from a dropper) on the Moon and other bodies compare to one on Earth? (indoors of course!)
Searching for "volume of a drop of water from an eyedropper", I ran across this answer on Quora:
It depends on the size of the dispensing tip, but generally for a Pasteur pipette it is ...
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What is the gravity in the center of Earth?
Let's suppose the earth is a perfect sphere and let's ignore its rotation and movement.
What would happen if I would be in the center of the earth? Would the gravity be zero in any direction so I ...
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Is it possible to determine if a planet can have a moon based on its mass and gravitational pull?
I'm curious, if based on what we know with Newton's law, can we determine if a random planet, knowing it's mass and gravitational pull, can hold a moon in it's orbit.
Or to phrase it another way, is ...
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If the Earth rotated slower about its axis, would your apparent weight increase or decrease?
The title above was a question on an exam that was marked wrong for me. I answered that if the Earth rotated slower (i.e. longer days), my apparent weight would increase. I based this on the ...
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On the tidal heating of a moon. What is the second Love number?
Years ago it was asked here how to calculate the tidal heating of a moon orbiting another body with a simple equation. The answer is very detailed. They explain the equation, its shortcomings, the ...
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Is $F=mg$ derived from Newton's law of universal gravitation $F=Gm_1m_2/r^2$?
If so, that means gravity is only 9.8 m/s^2 at the surface of the earth?
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Change in $g$ effective due to rotation
$g$ effective at any latitude changes due to rotation of earth. Does it also change due to rotation when the body is at height or at depth or does it change only at the surface?
Edit: I am referring ...
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Correct explanation of tides [duplicate]
In the explanation of tides on earth there seem to be different versions for the second water bulge on the side opposite to the moon, while everybody seems to agree that the bulge on the moon side is ...
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Is Earth really flattened at the poles because of centrifugal force?
My question is pretty much all in the title. I was always told that our planet is flattened at its poles due to the centrifugal force generated by its own rotation. However I don’t see how centrifugal ...
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How does a gas giant planet hold it's spherical shape when it has tidally locked rotation in it's orbit around the Sun?
How does a gas giant planet hold its spherical shape when it has a tidally locked rotation in its orbit around its Sun? Wouldn't it fall apart without its gravitational pull from the rotation? How ...
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Possible non-negligible physical effects that relate planetary/lunar geometry and seismic activity such as earthquakes?
Could any forces from the moon, the planets or the sun in orbit hypothetically influence seismic events on earth? And if yes how to approximately calculate and compare the magnitude of the forces?
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Falling at the centre of the Earth
Let’s assume to drill a hole at Earth surface at the point P1. The hole passes throughout the centre of the Earth and finishes at the opposite side at the point P2. Let’s assume then that 1) Earth ...
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Did Newton derive Titius-Bode Law of the planets in his Principia? [closed]
In college I was taught that no one knows why the planetary orbits conform to the Titius-Bode Law.
Recently I read that Newton HAD figured that out in his Principia.
Right Now I can’t even find a ...
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