<span>Answer: Va = 7,625 m/s
Vb = 7,404 m/s
Given:
A = 486,000 m
B = 901,000 m
G = 6.67428E-11 m^3/kg-s^2
M = 5.9736E+24 kg
r = 6,371,000 m
Recall that you need the actual orbital distance from the *center* of the Earth, giving radius plus altitude:
rA = 6,857,000 m
rB = 7,272,000 m
Equation:
V = SQRT { GM / r }
Solve for A
Va = SQRT { [ (6.67428E-11 m^3/kg-s^2) * (5.9736E+24 kg) ] / (6,857,000 m) }
Va = SQRT { [ 3.9869 m^3/s^2 ] / (6,857,000 m) }
Va = SQRT { 58,144,202 m^2/s^2 }
Va = 7,625 m/s
Solve for B
Vb = SQRT { [ (6.67428E-11 m^3/kg-s^2) * (5.9736E+24 kg) ] / (7,272,000 m) }
Vb = SQRT { [ 3.9869 m^3/s^2 ] / (7,272,000 m) }
Vb = SQRT { 54,826,016 m^2/s^2 }
Vb = 7,404 m/s</span>
This theory states that the outer rigid layer of the earth or the lithosphere is divided into a couple of dozen "plates" that move around across he earth's surface relative to each other. That is why Alfred Wegener noticed that Africa and South America seem to fit together.
Though Wegener's hypothesis lacked a geological mechanism to explain how the continents could drift across the earth's surface as he proposed.
