Why do astronauts (and cans of soft drink) float around in the shuttle instead of falling?

Astronauts only float around in the shuttle when they are outside the gravitational pull of the earth

Explanation: when astronauts takes off from the earth, they get to a point (space) where the earth's gravity can no longer pull them. At this state, they experience weightlessness because there is no gravity. Since there is no gravity to pull them down, hence they start floating.

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