Question

the ocean high tides will be lowest, that is at neap tide, when

a. the phase of the moon is a full moon.
b. the phase of the moon is three-quarter moon.
c. earth is farthest from the sun.
d. the phase of the moon is a new moon.

Explanation:

Define spring and neap tides

Tides are caused by the gravitational pull of the Moon and the Sun on Earth's oceans. When the gravitational forces of the Sun and the Moon align, they reinforce each other, creating exceptionally high high tides and low low tides, known as spring tides. When these forces act at right angles to each other, they partially cancel each other out, resulting in the lowest high tides and highest low tides, known as neap tides.

Identify moon phases for neap tides

Neap tides occur when the gravitational pulls of the Moon and the Sun are perpendicular (at a \(90^\circ\) angle) relative to Earth. This alignment occurs during the quarter moon phases: the first-quarter moon and the third-quarter (or last-quarter) moon.

Evaluate the given options

• Option A: A full moon alignment creates a straight line with Earth and the Sun, resulting in spring tides (highest high tides).
• Option B: A three-quarter moon (third-quarter moon) represents a perpendicular alignment, resulting in neap tides (lowest high tides).
• Option C: Earth's distance from the Sun affects overall tidal ranges slightly over the year but does not define the bi-weekly neap tide cycle.
• Option D: A new moon alignment creates a straight line with Earth and the Sun, resulting in spring tides.

Answer:

• (A) the phase of the moon is a full moon.
• (B) the phase of the moon is three-quarter moon. (Correct answer)
• (C) Earth is farthest from the sun.
• (D) the phase of the moon is a new moon.