Which tide is caused by gravitational and inertial interaction of the moon and Earth?

• A. Mean Sea Level
• B. Meteorological Tide
• C. Flood Current
• D. Lunar Tide

Answer: (D)

Tides arise from the gravitational pull of the Moon (and also the Sun) on Earth’s oceans. The Moon’s gravity pulls on the near side more strongly, creating a bulge toward the Moon, while inertia keeps water on the far side moving more independently, creating a second bulge on the opposite side. As the Earth rotates, different areas pass under these bulges, producing high and low tides. The tides caused specifically by the Moon’s gravity are called lunar tides, so this is the best description for the phenomenon described. Mean Sea Level is simply a reference level, not a dynamic tidal effect; a meteorological tide isn’t a standard term in tidal science; a flood current refers to flow in rivers, not ocean tides.