Final answer:
The force of gravity between an astronaut on a spacewalk and the space shuttle is not affected. The perception of weightlessness by astronauts in space is due to their state of free fall.
Step-by-step explanation:
In space, when an astronaut is on a spacewalk and is moving away from the space shuttle, the force of gravity between the two objects is not affected. Gravity is a fundamental force that acts between any two objects with mass, regardless of their distance from each other. However, the perceived lack of gravity experienced by astronauts in space is due to the fact that they are in free fall.
When an astronaut is in space, they are essentially constantly falling towards the Earth, but they are also moving fast enough horizontally sideways that they keep missing it.
This creates a continuous state of free fall, where the astronaut and the space shuttle are both being pulled towards the Earth by gravity, but they are also moving horizontally fast enough to stay in orbit around it. As a result, they experience a sensation of weightlessness because they are constantly falling towards the Earth along with the space shuttle.
So, even when an astronaut is moving away from the space shuttle during a spacewalk, the force of gravity between them remains the same. However, their perception of gravity is influenced by their state of free fall and their motion relative to the space shuttle.