Astronauts feel weightless because spacecraft and occupants fall together with the same gravitational acceleration. Gravity is not absent; it supplies orbital centripetal acceleration.

Apparent weight is the support/normal force. In continuous free fall it is approximately zero. Small residual accelerations create microgravity.

A spacecraft and its astronauts in orbit fall freely together under gravity. Gravity at orbital height is not zero; it supplies the centripetal acceleration that continually changes their direction. A scale reads the support or normal force, so an astronaut floating relative to the craft has nearly zero apparent weight even while the true gravitational force mg remains. The same local effect occurs in a freely falling lift during the ideal falling interval, ignoring air drag. Astronaut mass does not vanish. The orbit is a curved free-fall trajectory with sufficient sideways velocity, not an escape from Earth’s field.

Worked example: At orbital radius 2R, ideal g is one quarter surface g, not zero, yet a freely floating astronaut has near-zero scale reading.

NCERT trap: Weightlessness means nearly zero support force, not zero gravitational field or zero inertia.

NEET method: Draw gravity on craft and person, then ask what contact force a scale must supply.

Reading estimate excludes the checks and retake.

Gravitation

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