Question:

At what height from the surface of earth the gravitation potential and the value of g are -9.4 × 10⁷ Jkg⁻¹ and 6.0 ms⁻² respectively?

1600 km

1400 km

2600 km

2000 km

V = -GM/(R+h) = -9.4 × 10⁷ (1)
g = GM/(R+h)² = 6.0 (2)
Dividing the two equations, we get:
→ 5.4 × 10⁷(R+h) = 6
→ R+h = 9000 km
→ h = 2600 km