Final answer:
A person in an artificial satellite of the Earth feels weightless because they are falling freely, while a person standing on the moon has weight due to the moon's weaker gravity.
Step-by-step explanation:
An object's weight depends on the acceleration due to gravity. Weight is the force that gravity exerts on an object and is directly proportional to the object's mass. On the moon, the gravity is weaker than on Earth, so a person standing on the moon would have less weight compared to when they are on Earth.
Weightlessness refers to the feeling of no gravitational force acting on an object. When a person is in an artificial satellite around the Earth or in an elevator whose cable has broken or in an airplane whose engines no longer work, they are falling freely, resulting in a sensation of weightlessness.