Author Question: What would the tides on Earth be like if Earth had two moons identical in size and orbit except that ... (Read 59 times)

bio_gurl · **on:** Jul 16, 2018

What would the tides on Earth be like if Earth had two moons identical in size and orbit except that they were 180 degrees apart? What if they were 90 degrees apart?

What will be an ideal response?

Question 2

Explain why a floating object moves slowly in the direction of wave movement.

What will be an ideal response?

bhavsar · **Reply #1 on:** Jul 16, 2018

Answer to Question 1

If the two moons were 180 degrees apart, then the moons' gravitational pulls on solid Earth would cancel each other and Earth would not be pulled more toward either moon. The forces exerted by the moons on the ocean surface would also partly counteract one another, although the ocean surface would still rise slightly toward each moon because the water on the side facing a moon is more strongly affected by that moon than it is by the moon on the opposite side of Earth.
If the moons were positioned 90 degrees apart the lunar forces would cancel each other out and Earth's oceans would only experience tides due to the sun.

Answer to Question 2

Since the source of the wave energy is the wind blowing across the ocean surface, the amount of wave motion decreases downward from the surface. When a wave passes, the rising-and-forward-moving part of the circular motion imparted to the water is closer to the surface than the sinking-and-backward-moving part of the motion. This results in a floating object moving forward a small amount in the direction of wave movement.