Question

2. Wegener’s idea that tidal forces might cause continental drift was shown to be impossible when it was ____.
A. determined that Earth’s magnetic field was too strong
B. shown that the tidal forces needed to move continents would stop Earth’s rotation
C. determined that Earth’s density was too low
D. shown that no tides occurred 200 million years ago

Answer 1

The correct answer that would best complete the given statement above would be option B. Wegener’s idea that tidal forces might cause continental drift was shown to be impossible when it was shown that the tidal forces needed to move continents would stop Earth’s rotation. Hope this answer helps.

Answer 2

The correct answer is option B. shown that the tidal forces needed to move continents would stop Earth’s rotation.

The Wegener’s idea that tidal forces might cause continental drift suggested that the tidal force and the centrifugal forces on the earth was the cause of the movement of the plates.

But, he was unable to propose the mechanism of such movement. Also, if the centrifugal force of the earth would move the plates apart, then the earth below it should remain stationary, but the earth is in continuous rotation, so, this idea was not acceptable, as it is would stop rotation of earth.