Tagged Questions
1
vote
2answers
55 views
Will a spinning object come to rest?
Will a sphere spinning on its own axis come to rest given enough time, provided no other forces act upon it?
I know that if you have two spinning spheres in the depths of space and orbiting each ...
11
votes
2answers
198 views
How large can planets or moons appear?
In many artistic impressions or movies there are pictures or scenes where the sky is filled with an enormous moon (as seen from a planet) or vice versa.
I wonder if there is an upper limit to the ...
6
votes
3answers
171 views
Falling through the rotating Earth
Suppose you were standing on the rotating Earth (not necessarily Equator or the poles) and suddenly your body lost the ability to avoid effortlessly passing through solid rock.
Because the earth's ...
3
votes
3answers
187 views
Does Kepler's law only apply to planets?
Does Kepler's law only apply to planets? If so why doesn't it apply to other objects undergoing circular motion?
By Kepler's law I'm referring to $T^2 \propto r^3$
2
votes
1answer
74 views
How should I be thinking about tides?
I am working on a project for physics that involves tides. This is my current mind set when thinking about tides:
The earth applies a gravitational force on some mass ...
3
votes
3answers
534 views
How do the Planets and Sun get their initial rotation?
How do the Planets and Sun get their initial rotation?
Why do Venus and Mercury rotate so slowly compared to other planets and why does Venus rotate in a different direction to Mercury, Earth and ...
2
votes
1answer
85 views
Synchronising the Earth's rotation via mass redistribution
How much material would have to be moved per year from mountain-tops to valleys in order to keep the Earth's rotation synchronised with UTC, thus removing the need for leap seconds to be periodically ...
13
votes
9answers
3k views
Why are orbits elliptical?
Almost all of the orbits of planets and other celestial bodies are elliptical, not circular.
Is this due to gravitational pull by other nearby massive bodies?
If this was the case a two body system ...
