What type of tide occurs when the Sun and Moon are at right angles in the sky?

• A. Spring
• B. Neap
• C. High Tide
• D. Low Tide

Answer: (B)

Tides are caused by the gravity of both the Moon and the Sun acting on Earth's oceans. The Moon has the larger local effect because it is much closer, while the Sun’s gravity also contributes.

When the Sun and Moon line up with Earth, their gravitational pulls reinforce each other, giving a larger difference between high and low tides—this is a spring tide. But when the Sun and Moon are at right angles in the sky, their tidal effects partially cancel each other out. The bulges in the oceans are weaker, so the difference between high and low tides is smaller. This situation is a neap tide.

So, the configuration described—Sun and Moon at right angles—produces a neap tide, not a spring tide. High and low tides are still the daily extremes, just with a smaller range during a neap tide.