Question

A particle weighs 120 N on the surface of the earth. At what height above the
earth's surface will its weight be 30 N? Radius of the earth is 6400 km. ​

Answer 1

Answer:

6400 km.

Explanation:

120 = mg

30 = mg'

120/30 = 4 = g/g' = GmM/R² ÷GmM/(R+h)² = (R+h)²/R²

R+h = 2R

R = h

h = R = 6400 km.