1

. See, for example, Frank D. Stacey, Physics of the Earth (New York: John Wiley & Sons, Inc., 1969), pp. 281–282.

2

. The mass expelled from Earth during the flood was probably less than 2.8 × 10²⁴ grams, less than 1/2,000 the mass of the Earth. [See Table 29 on page 429.] Therefore, that lost mass can be neglected. Even if it could not be neglected, it would have only a secondary effect, because the loss of that mass would not alter Earth’s spin rate.

3

. Only a very small fraction of the preflood Earth’s potential energy was expended in increasing the Earth’s rotational kinetic energy. The Earth’s angular velocity today is   

so the rotational kinetic energy gained by Earth as a result of its faster spin rate (but lower polar moment of inertia) after the flood is relatively trivial and can be neglected.  Endnotes 2 and 3 above may seem contradictory to some people. The ice skater shown in Figure 79 on page 143 will spin faster as she pulls her arms in toward her spin axis. However, even if something as heavy as her arms (while extended) suddenly flew off her spinning body, her spin rate would remain about the same.

.

4

. This factor of 5 can be estimated by calculating the ratio of the energy released by gravitational settling just within the outer core (Dr  g  V  h) to the energy expended in melting (L  V  r_av), where

Dr = the average density difference between particles that sink to the particles that float,

g = the average acceleration of gravity in the core,

V = the volume of melted rock in the outer core,

h = the average “fall distance” (about half the radius of the outer core),

L = the heat of fusion in the outer core, and

r_av = average density of the melted particles.

If           g = 500 cm/sec²                    h  =  1,750  × 10⁵  cm

              L = 4 × 10⁹ ergs/gm         

then this dimensionless ratio is about 5. 

Any ratio that is much greater than 1.0 will produce runaway heating near the center of the Earth. (Other minor effects are being omitted.) From this analysis, it becomes clear that this factor is large because h (the “fall distance”) is so large. With about 5 times more heat in the core than it takes to melt the outer core, heat from the outer core should be conducting today into and melting the base of the mantle.

5

. Don L. Anderson, Theory of the Earth (Boston: Blackwell Scientific Publications, 1989), p. 68.