At height h above the surface of Earth, the gravitational acceleration is What is h? Note: The radius of Earth is 6380 km.

The acceleration of gravity is inversely proportional to

the square of the distance from Earth's center.

The acceleration of gravity is 9.8 m/s² on the Earth's surface ...

6380 km from the center.

If the acceleration of gravity at 'h' is 4.9 m/s² ... 1/2 of what it is

on the surface, then the distance from the center is

(6380 x √2) = 9,023 km (rounded),

and 'h' is the distance above the surface

= (9,023 - 6,380) = 2,643 km (rounded).