UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
Home
How it Works
Ask a Question
Search Topics
Webcasts
Our Scientists
Science Links
Contact Information
Why a mass of 1 kilogram will have a different weight on the moon?
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.



Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2015 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use