Final answer:
As a body moves higher above the Earth's surface, its weight decreases due to the reduction in gravitational force with distance, but the mass of the body remains constant.
Step-by-step explanation:
When a body moves higher and higher above the surface of the Earth, its weight decreases. This happens because weight is a measure of the force of gravity acting on an object's mass, and this force diminishes with distance from the Earth's center due to the inverse-square law. As you go higher, there is less mass between you and the center of the Earth, leading to a decrease in the gravitational pull and consequently in your weight. For instance, astronauts on the Moon experienced much less gravity because the Moon's gravitational acceleration is only 1.625 m/s² compared to Earth's 9.80 m/s², resulting in them weighing less on the Moon. This principle also applies as you travel away from Earth. However, an object's mass remains unchanged regardless of its location because mass is an intrinsic property of the object and does not depend on gravity.