Tides
Because of the gravitational attraction of the Moon and a lesser degree of the Sun, the
oceans and the seas oscillate with a risings (flood tide) and lowering (ebb tide) of their level.
The simulation shows an Earth uniformly covered with water, the level of which is linked
to the relative Earth - Moon and Earth - Sun positions.
The centrifugal force due to the rotation of the system Earth - Moon around their
centre of mass acts on the ocean level. This force acts on the opposite
side in respect to the force of attraction. In the simulation the forces are
represented by vectors.
The maximum variation of the level happens when the Moon and the Sun are on the same line
(spring tides), while the minimum variation happens when the Moon and the Sun are disposed at a right
angle with respect to the Earth (neap tide).
Button shows the vectors that represent
the force of attraction between Earth and Moon.
Button shows the vectors that represent
the centrifugal forces.
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