The earth's rotation rate is slowing down because of friction against the tidal bulges caused by the gravitation of the moon (major factor) and the sun (lesser factor). The earth's rotational energy is dissipated as heat, but where is the angular momentum going, and what physical mechanism brings that momentum there?
(In reply to
I disagree by Ken Haley)
Ken,
Perhaps you are confusing momentum or, in this case, angular momentum
with energy. Angular momentum is always conserved. Always.
I'm not sure what you mean by dissipated to "the motion of the fluids
on earth". And heat is a form of energy... not angular momentum.
Angular momentum CAN be transferred, but it is conserved. And in
your example of spinning a raw egg: the act of your spinning the
egg imparts an exact opposite angular momentum to the earth system
(through your hand, the rest of you, and through your feet, to
everything on the Earth). Incidentally, you are also giving the egg rotational kinetic energy at a loss to your stored chemical energy.
As the egg slows down due to friction with the table top (and perhaps
air resistance), the ENERGY will be converted to heating the egg
slightly, perhaps the table top slightly, the air slightly, and perhaps
a little bit of the egg fluids from internal disturbances.
But all of the ANGULAR MOMENTUM is negated by an exact opposite change
of momentum to the earth system (through the tabletop, the table legs,
the floor, etc.).
With respect to the earth having no moon: barring any external
influence with which to interact (such as another planet, satellite,
asteroid, or sun), that is correct... no matter how much heating of the
oceans or weather occurs, the planet system (its occupants water, air,
clouds, humans) will retain exactly their total angular momentum.
- ThoughtProvoker
re: I disagree - me too, with you
