模型地球内部引力图
地球模型计算的引力外地核处引力最大,外地核向内或向外均在减小，从地核核心区处逃离地球引力需要能量为W=,由于不均匀分布，势能增加了
实际引力为分层球体的引力标准线叠加的结果。
如果地球模型不错我们完全可以根据分层密度计算它的内引力图
半径R
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密度
R/N 1
分层密度
把密度确定以后，我们再把密度分层，先按最小密度绘制大圆图，再 把第二层密度减去第一层后绘图，如此循环，画到地核，再把所有值叠加起来，就是模型引力图了。。如果模型不错，那么地球的实际引力就会和所画图一样。 当
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44????aa221?a?1?a?????3g03MG33g(a)?1?2a??=?1?2a??332?2R?2?2222??(1?a)?1(1?a)?1????
????a?sin?,Rsin?为质点到球心的距离,g0为地表重力加速度AUTOcadvba模型程序代码
Sub 地球引力模型() Dim ml As Object
Dim a As Variant, a1 As Variant, a2 As Variant, a3 As Variant, a4 As Variant
Dim v As Variant, v1 As Variant, v2 As Variant, v3 As Variant, v4 As Variant, v5 As Variant
Dim U As Variant, U1 As Variant, U2 As Variant, U3 As Variant, U4 As Variant
Dim co As Variant co = 3
Dim p(0 To 20001) As Double Dim i As Integer Dim J As Variant
a = : a1 = : a2 = : a3 = : a4 = b = : b1 = : b2 = : b3 = : b4 = For i = 0 To 10000 Step 2
v = i / 1000: v1 = v * a: v2 = v * a1: v3 = v * a2: v4 = v * a3: v5 = v * a4 p(i) = i If v1 <= 1 Then
U = 750 * b * (1 + v1 * 2 - (1 - v1 ^ 2 + (v1 ^ 4) / 3) / (1 + (1 - v1 ^ 2) ^ ) / a
ElseIf v1 > 1 And v1 <= a Then
U = 500 * b * a ^ -3 / v ^ 2 ElseIf v1 > a Then U3 = 0 End If If v2 <= 1 Then
U1 = 750 * b1 * (1 + v2 * 2 - (1 - v2 ^ 2 + (v2 ^ 4) / 3) / (1 + (1 - v2 ^ 2) ^ ) / a1
ElseIf v2 > 1 And v2 <= a1 Then U1 = 500 * b1 * a1 ^ -3 / v ^ 2 ElseIf v2 > a1 Then U3 = 0 End If If v3 <= 1 Then
U2 = 750 * b2 * (1 + v3 * 2 - (1 - v3 ^ 2 + (v3 ^ 4) / 3) / (1 + (1 - v3 ^ 2) ^ ) / a2
ElseIf v3 > 1 And v3 <= a2 Then U2 = 500 * b2 * a2 ^ -3 / v ^ 2 ElseIf v3 > a2 Then U2 = 0 End If If v4 <= 1 Then
U3 = 750 * b3 * (1 + v4 * 2 - (1 - v4 ^ 2 + (v4 ^ 4) / 3) / (1 + (1 - v4 ^ 2)
^ ) / a3
ElseIf v4 > 1 And v4 <= a3 Then U3 = 500 * b3 * a3 ^ -3 / v ^ 2 ElseIf v4 > a3 Then U3 = 0 End If If v5 <= 1 Then
U4 = 750 * b4 * (1 + v5 * 2 - (1 - v5 ^ 2 + (v5 ^ 4) / 3) / (1 + (1 - v5 ^ 2) ^ ) / a4
ElseIf v5 > 1 And v5 <= a4 Then U4 = 500 * b4 * a4 ^ -3 / v ^ 2 ElseIf v5 > a4 Then U4 = 0 End If If v <= 1 Then
p(i + 1) = 750 * (1 + v * 2 - (1 - v ^ 2 + (v ^ 4) / 3) / (1 + (1 - v ^ 2) ^ ) + U + U1 + U2 + U3 + U4 Else
p(i + 1) = 500 * (1 + b * a ^ -3 + b1 * a1 ^ -3 + b2 * a2 ^ -3 + b3 * a3 ^ -3 + b4 * a4 ^ -3) / v ^ 2 End If Next i
Set ml = co = co + 1 = co
End Sub 精心搜集整理，只为你的需要
地球引力模型程序代码
