Answer to Question 1
Ice is slightly less dense than water, so it floats. An iceberg sinks in water until it displaces a volume of water whose weight is equal to that of the ice. When the iceberg has sunk to an equilibrium position, only about 10 of its volume is above water level. If some of the ice above water level should melt, the iceberg rises to maintain equilibrium with the same proportion of ice above and below the water.
Earth's crust is similar to the iceberg in that it sinks into the mantle to its equilibrium level. Where the crust is thickest, as beneath mountains, it sinks farther down into the mantle and it also rises higher above the surface. And because continental crust is thicker and less dense than oceanic crust, it stands higher than the ocean basins.
Answer to Question 2
(1 ) The continent remained fixed and the north magnetic pole moved; (2 ) the north magnetic pole stayed still and the continent moved; (3 ) both the continent and north magnetic pole moved. The correct explanation is that both the continent and north magnetic pole moved.
The Tilt of Earth’s Axis
Earth’s orientation
The rock cycle and the Earth’s physical environment
The Principle of Falsifiability
The Distribution of Water on Earth
When viewed from the Earth, Venus subtends an angle of about 1 arcminute (1/60°) when it is at ...