What are the difference between mass and weight? I keep getting confused in my physics class, and I am in 8th grade. Thank you in advance.


Mass is a measure of how much matter (atoms) make up an object. Weight is a force that results from that quantity of matter accelerating in a gravitational field. Weight = mass*acceleration due to gravity. Weight can change depending on what gravitational field you are in, mass cannot change.

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    $\begingroup$ Incorrect. 100 atoms of copper do not have same mass as 100 atoms of uranium although both have the same number of atoms. $\endgroup$ Nov 16 '17 at 4:44
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    $\begingroup$ Didn't say that mass is the number of atoms. It's an 8th grade level answer to and 8th grade level question. $\endgroup$ Nov 16 '17 at 5:37

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