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Learn about planets outside our solar system through Exoplanets and Alien Solar Systems by Tahir Yaqoob, Ph.D., a book in our online store book collection.
Which would be more difficult to pull? Well, we really shouldn’t be treating these animals this way! Please do not pull elephants or mice!
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What is mass?

Would it be more difficult to pull an elephant or a mouse?
If you pulled each animal with the same amount of force, the elephant would respond less to pulling, even if he didn’t pull back at all. That’s because an elephant has more mass than a mouse.

Mass is the amount of material in an object. Mass stays the same no matter what force is acting on the object. This makes mass different from weight, which depends on both the amount of mass and the amount of gravity. This means that even though our elephant weighs less on the moon, his mass stays the same.


Last modified September 10, 2002 by Lisa Gardiner.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA