An electron with speed 0.8c, has a rest energy of .51MeV.(adsbygoogle = window.adsbygoogle || []).push({});

What are its mass, its momentum, and its enegy (including rest energy)?

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Ok, isnt it possible to get the three answers without using the .5MeV ?

I have 3 formulas for mass, momentum and total energy that dont use the .5Mev

but then I feel like I might be doing something wrong since they gave me the value.

Im not sure how to post the forumlas, but they are on this page

http://galileo.phys.virginia.edu/classes/252/energy_p_reln.html

thanks for any help

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# Homework Help: Total energy, mass, and momentum.

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