Zero Gravity PointHardQuestion 30719
Question
Between Earth (mass M) and Moon (mass m, distance d apart), the point where net gravitational field is zero lies at distance x from Earth where:
- Ax = d/(1 + √(M/m))
- Bx = d√M/(√M + √m)Correct
- Cx = d×M/(M+m)
- Dx = d/(1 + m/M)
Correct answer
x = d√M/(√M + √m)
Explanation
GM/x² = Gm/(d−x)². Taking square roots: √M/x = √m/(d−x). Cross multiply: (d−x)√M = x√m → d√M = x(√M + √m) → x = d√M/(√M + √m).