Why does the Moon's gravity have a greater effect on earths oceans tides then the suns gravity?

Answer 1

-- The forces of gravity between two masses are inversely proportional to

the square of the distance between the masses, and directly proportional

to the product of the masses.

-- The sun is about 390 times as far from us as the moon is.

-- The square of 390 is 152,690.

-- So each little pellet of mass in the moon attracts each little pellet of water on

Earth 152,690 times as strongly as the same size pellet of solar mass does.

-- The sun has 27.08 million times as much mass as the moon has. So all the

pellets in the sun put together attract each little pellet of water on the Earth

27.08 million times as strongly as the whole moon would if it were at the same

distance from us as the sun is.

-- Put these two together, and you have 27.08 million times stronger, divided by

152,690 times weaker, = 177.4 times as much force in favor of the sun.

Surprise! The sun actually has a greater effect on the tides than the moon does.

Answer 2

The Moon is closer to Earth than the Sun, so its gravitational force has a stronger effect on the tides. Additionally, the Moon's gravitational pull directly affects the water on Earth due to its proximity, leading to larger tidal bulges in comparison to the Sun's influence.