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Why a mass of 1 kilogram will have a different weight on the moon?
Question Date: 2013-01-13
Answer 1:

The mass of on an object is basically the amount of "stuff" (or more properly, the amount of matter) in that object. Technically a kilogram is a unit of mass, not weight. Weight is the force experienced by that object due to the acceleration of gravity. Force is equal to mass times acceleration (F=m*a) and is measured in newtons (1 newton = 1 kg*m/s2). On Earth´s surface the acceleration is due to gravity is 9.8 m/s2. So an object with a mass of 1 kilogram has a weight of 9.8 newtons.

The acceleration due to gravity on a given planet depends on the mass and radius of that planet. (Specifically, g=GM/r2, where g is acceleration due to gravity, G is a universal gravitation constant, M is the mass of the planet, and r is the radius of the planet.) Because the Moon has less mass than the Earth, gravitational acceleration (and hence, weight) is less on the Moon than on Earth.

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