Tides are the rise and fall of sea levels caused by the combined effects of which forces?

Tides are the rise and fall of sea levels caused by the combined effects of which forces?

• A. Gravitational forces exerted by the Moon, the Sun, and the rotation of Earth
• B. Wind and water temperature changes
• C. Underwater earthquakes
• D. Ocean floor spreading

Answer: (A)

Tides come from the gravitational pull of the Moon and the Sun on Earth’s oceans, with the planet’s rotation helping move those bulges around the globe. The Moon’s gravity pulls on the near side to create a bulge there and, due to inertia, a second bulge forms on the far side as well. The Sun, though much farther away, is also massive enough to tug on the oceans and influence tide strength. Because Earth is rotating, these bulges move with the surface under coastlines, producing the familiar high and low tides. When the Sun and Moon line up, their gravitational effects amplify tides (spring tides); when they’re at right angles, they partially cancel, producing weaker tides (neap tides). The other options point to phenomena like wind-driven water level changes, tsunamis from earthquakes, or tectonic plate movement, which aren’t the regular, gravity-driven rise and fall of tides.

Tides come from the gravitational pull of the Moon and the Sun on Earth’s oceans, with the planet’s rotation helping move those bulges around the globe. The Moon’s gravity pulls on the near side to create a bulge there and, due to inertia, a second bulge forms on the far side as well. The Sun, though much farther away, is also massive enough to tug on the oceans and influence tide strength. Because Earth is rotating, these bulges move with the surface under coastlines, producing the familiar high and low tides. When the Sun and Moon line up, their gravitational effects amplify tides (spring tides); when they’re at right angles, they partially cancel, producing weaker tides (neap tides). The other options point to phenomena like wind-driven water level changes, tsunamis from earthquakes, or tectonic plate movement, which aren’t the regular, gravity-driven rise and fall of tides.