Astronomy Practice Exam

What are spring tides characterized by?

1. Moderate tides

2. Very strong tides

3. Minimal tides

4. Tidal stagnation

The correct answer is: Very strong tides

Spring tides are characterized by very strong tides, which occur when the gravitational forces of the Moon and the Sun align with the Earth's position in relation to them. This alignment happens during the new moon and full moon phases. When the Sun and Moon are on the same side of the Earth (new moon) or on opposite sides (full moon), their gravitational pull works together, resulting in higher high tides and lower low tides. This combined effect causes a significant difference in tidal ranges, hence the occurrence of very strong tides. In contrast, moderate tides occur at other phases of the lunar cycle, and minimal tides, also known as neap tides, occur when the Moon is at the first or third quarter phase, where the Sun and Moon are at right angles relative to the Earth, reducing their combined gravitational effect. Tidal stagnation, while related to tidal behavior, does not describe the intense variations seen during spring tides. Thus, the distinctive feature of spring tides is their high strength, making the answer very clear as indicating very strong tides.