Question

Why a spring tide occurs in full moon and no moon days?

Answer 1

Spring tides occurs during the full moon and the new moon. During the moon's quarter phases the sun and moon work at right angles, causing the bulges to cancel each other. They occur when the gravitational forces of the Moon and the Sun are the perpendicular to one another with respect to the Earth.

Answer 2

Spring tide occurs due to the gravitational force between the sun and the moon, the tidal effect of the moon on our earth is twice stronger than the sun.

Explanation:

The moon is much nearer to that of the sun hence the tidal effects of the moon are higher. The gravitational force of the sun and moon makes the oceanic water rise up (pulls up) creating an oceanic bulge. This phenomenon results in the creation of high tides in the area facing the moon.

Meanwhile, in the other parts, the oceanic water slips away to fill in the bulge, creating low tidal areas. It follows a lunar day and not a solar day.