1. The driving force behind the movement of B is due to the fluid becoming leading to the fluid . As it cools at the top, the fluid becomes and starts .

2. The movement seen in this diagram is driven by energy from .

3. At the point labeled B, one layer inside the earth is moving. This is an example of .

4. The changes occurring in B that cause it to move are primarily .

5. The description of this model explains that it’s a timelapse of events happening inside of the earth. Why does the model use a timelapse, instead of showing the change in real time?

• In real time, these processes are happening too fast for us to be able to observe.
• The processes shown in this model are exaggerated and there is actually so little movement inside the Earth that it has no effect.
• The timelapse helps to show greater detail inside the earth, so we can observe changes that are occurring over a short period of time.
• In real time, these processes are happening too slowly for us to observe the phenomenon in this model.

6. Use the image below to draw an arrow in the direction of heat transfer between C and B.

7. At letter C, we see the intersection of two different layers that are touching. What form of energy transfer is likely driving the movement we see in B?

• convection
• radiation
• conduction

8. Circle two points on this diagram where the earth’s interior and the exterior exchange matter.

9. Explain 2 effects that you expect Layer B to have on Layer A.

10. Explain 2 effects that you expect Layer A to have on Layer B.