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The Spring 2011 issue of The Earth Scientist is focused on modernizing seismology education. Thanks to IRIS, you can download this issue for free as a pdf. Print copies are available in our online store.
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 the same amount, the mouse would come towards you but the elephant would not move at all, even if he didn’t try to pull back. That’s because an elephant has more mass than a mouse.

Mass is the amount of stuff in an object. It is different from weight because weight depends on 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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