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I am a little puzzled by the following:
The moon in causing Earth tides causes the Earth to generate heat loss due to friction and slows down the Earth rotation. This decreases the angular momentum of the earth. The angular momentum of the Earth and moon system combined cannot change. So the moon and Earth have to increase their angular momentum. It is said that they do this by increasing their radii of rotation about the earth-moon centre of mass: the Earth and moon have to move farther apart.
I don't see how that can happen. Since the moon acquires greater potential energy, this compensation for loss of angular momentum takes energy. Where is the energy supposed to come from?
Would the Earth not simply develop more of a wobble to provide the needed angular momentum?
AM
The moon in causing Earth tides causes the Earth to generate heat loss due to friction and slows down the Earth rotation. This decreases the angular momentum of the earth. The angular momentum of the Earth and moon system combined cannot change. So the moon and Earth have to increase their angular momentum. It is said that they do this by increasing their radii of rotation about the earth-moon centre of mass: the Earth and moon have to move farther apart.
I don't see how that can happen. Since the moon acquires greater potential energy, this compensation for loss of angular momentum takes energy. Where is the energy supposed to come from?
Would the Earth not simply develop more of a wobble to provide the needed angular momentum?
AM