Final answer:
This question is about the variation in weight observed in different gravitational fields. An astronaut's pack weighs less on the moon due to its lower gravity. However, her mass remains constant as mass is independent of gravitational pull.
Step-by-step explanation:
The subject matter of this question falls within the realm of physics. Specifically, it addresses concepts entailing gravitational force and the difference in weight measured on different celestial bodies. Weight, which refers to the force that gravity exerts on an object, is directly proportional to the mass of the object. However, it changes with the change in gravitational force while the mass remains constant.
An astronaut's pack that weighs 18.5 Newtons on Earth weighs only 3.24 Newtons on the moon because the moon's gravity is about one-sixth that of Earth's. This is corroborated by the empirical formula that defines the weight of an object as the product of its mass and the acceleration due to gravity. Since acceleration due to gravity on the moon (1.67 m/s²) is much less than that on Earth (9.80 m/s²), the astronaut's pack weighs considerably less on the moon than it does on Earth despite the pack's mass remaining unchanged.
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