Explain how a P-wave shadow will form. Between which degrees will ...

[torybrooks]

Explain how a P-wave shadow will form. Between which degrees will it form?
 
  What will be an ideal response?

Question 2

What are the three main mechanisms of convective flow in the outer core?
 
  What will be an ideal response?

[Koolkid240]

Answer to Question 1

Answer: As P waves pass through layers of differing densities, the wave paths will refract and thus change the direction that the waves are traveling, which can result in some areas not receiving P waves. The shadow will form between 100 and 140 degrees.

Answer to Question 2

Answer:
1. Heat conducts out of the core into the mantle, making the material in the outermost core cool, solidify, and sink.
2. Crystallization of solid iron near the bottom of the core that adheres to the inner core leaves low-density fluids behind. These rise toward the mantle, resulting in chemical convection.
3. Radioactive isotopes decay, providing additional heat to drive thermal convection.