What happens to the mass and weight of an object lifted to an altitude equal to the radius of a planet?

When an object is lifted to an altitude equal to the radius of a planet, its mass remains unchanged because mass is an intrinsic property of matter that does not depend on location. Whether an object is on the surface of a planet or at a height equal to the radius of the planet, its mass stays the same.

However, weight, which is the force of gravity acting on an object, does change with altitude. Weight is calculated as the product of mass and the acceleration due to gravity. As you move away from the surface of the planet, the acceleration due to gravity decreases. Specifically, at an altitude equal to the radius of the planet, the gravitational force is half of what it is at the surface.

This reduction in gravitational pull results in a decrease in weight. Thus, although the mass of the object remains constant, its weight decreases as it is lifted to the specified altitude, making this the correct interpretation of the situation.