Asked in ETEA MDCAT 2012 2012Moderate

An object in a satellite orbiting around the earth is weightless because:

Correct answer: C. Its motion is free fall

  • A. g = 0
  • B. No force acts on it
  • C. Its motion is free fall
  • D. It is far away from the earth

Explanation

The correct answer is that an object in a satellite orbiting around the Earth is weightless because its motion is in free fall. In orbit, both the satellite and the objects inside it are in a constant state of free fall towards the Earth, but because they are moving forward fast enough, they keep missing it. This continuous free-fall condition results in the experience of weightlessness. While the force of gravity does act on the objects, the lack of a normal contact force, which we associate with weight, is what makes them feel weightless. This is different from the idea that gravity is zero or that no force acts on the object.

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