Earth's Formation Flashcards
0
Q
There was: \_\_\_\_\_\_ \_\_\_\_\_\_ \_\_\_\_\_ \_\_\_\_\_ In space from formation of the sun
A
Debris
Metals
Gases
Rocks
1
Q
How many years ago did Earth form?
A
4.5 billion years ago
2
Q
Accretion
A
Gravity pulls debris into a ball
3
Q
_____s went into the center of the Earth because they were ____er.
A
Metals
Denser
4
Q
_____ materials went to the outer parts of the Earth because they were less _____.
A
Rocky
Dense
5
Q
Molten = …
A
Melted
6
Q
It took ___ million years for Earth to form
A
100
7
Q
What two places does the heat inside the Earth come from?
A
Radioactive decay
Pressure
8
Q
Pressure = …
A
Residual heat
9
Q
Radioactive decay has what elements?
A
Thorium
Uranium
Potassium
10
Q
These radioactive elements do what to form radioactive decay?
A
Give off heat which travels outward towards surface
