An astronaut has a mass of 82.0 kg. What is the astronaut's stationary weight at a position 4230 kilometers above Earth's surface? Note: Earth's radius is 6380 km.

The acceleration of gravity is inversely proportional to the square of

the distance from the Earth's center. So out where the astronaut is,

the value of gravity will be

(9.81 m/s²) · (4230/6380) ² = about 4.31 m/s².

No matter where she is, her weight is always

(mass) x (gravity in that place)

= (82 kg) x (4.31 m/s²) = 353.6 Newtons