alleryStart learning →What supplies the power that keeps Earth's crustal plates moving?
ASteady pull of lunar gravity
BDaily spin of Earth's crust
CWind blowing across oceans
DSlow convection in the mantle
Answer & Solution
Correct answer: D. Slow convection in the mantle
1. Heat built up inside the planet has to escape towards the surface.
2. Warmer mantle material rises and cooler material sinks, which is convection.
3. That slow churning drags the plates along above it.
4. Lunar gravity raises tides in the ocean but does not drive the plates.
_Source: OpenStax Astronomy (CC BY 4.0), section 8.2 Earth’s Crust_
Keep practising Earth as a Planet
Browse all Earth as a Planet questions for CAST — California Science Test, or explore more Science topics.
Related questions
Sort the layers by where they sitThe Tunguska body carried the punch of a 5-megaton bomb, yet dug no crater. What explains About 2 square kilometers of new ocean floor form every year. What does that rate imply?A worldwide sediment layer from 65 million years ago is rich in which rare metal?Earth was struck as often as the Moon, yet shows far fewer craters. What removed them?Carbon dioxide warms Earth's surface because it absorbs which kind of radiation?The great ice ages were primarily the result of changes in what?Effects of the atmosphere that last through decades and centuries are given which name?