Consider an artificial satellite moving in a stable circular orbit around the Earth at a height equal to the radius of the Earth. What is the effective acceleration due to gravity experienced by objects inside the satellite?

💡 Solution & Explanation

The gravitational force at an altitude equal to the Earth radius is given by Newton law of gravitation where the distance from the center is doubled, resulting in gravity being reduced to one-fourth of its surface value. However, objects inside the orbiting satellite experience free fall toward the center of the Earth, exactly matching the centripetal acceleration required for orbital motion, leading to apparent weightlessness. Free fall cancels out support forces, but the actual gravitational field strength at that altitude is non-zero. The orbital radius in this case is twice the Earth radius.