Give a reason why the weight of an object varies from one planet to another?

The weight of an object varies from one planet to another because the gravitational pull of each planet is different. Gravity is what determines the weight of an object, so on a planet with a stronger gravitational pull, the object will weigh more, and on a planet with a weaker gravitational pull, the object will weigh less.

Gravity is the force of attraction between any two objects with mass. The greater the mass of an object, the greater its gravitational force. The weight of an object is the force of gravity acting on that object. The weight of an object will vary from one planet to another because the gravitational force of each planet is different. The gravitational force of a planet is determined by its mass and radius. Planets with greater mass and smaller radius will have greater gravitational force. Planets with smaller mass and larger radius will have weaker gravitational force.