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A comment on NASA engineer's 'helical engine' may violate the laws of physics. Parent comment

Re:NASA engineer's 'helical engine' may violate the laws of ... by zonidjan on Tuesday October 15, 2019 @04:59AM (#21256713)
So... you're saying E=mc^2 is false? Huh, who woulda thunk it.
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Re:NASA engineer's 'helical engine' may violate the laws of ... by gpderetta on Tuesday October 15, 2019 @06:18AM (#21257103)
IANAP, but as far as I know it is true only if m is the relativistic mass which apparently is an obsolete and confusing concept which is not taught anymore (according to Wikipedia Einstein himself disliked it). Otherwise the formula only holds at rest.
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Re:NASA engineer's 'helical engine' may violate the laws of ... by semajian on Tuesday October 15, 2019 @06:47AM (#21257229)
Yes, well said.
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Re:NASA engineer's 'helical engine' may violate the laws of ... by antonvs on Wednesday October 16, 2019 @05:01PM (#21275636)
It's a simplified equation which only fully applies in the case where momentum is zero.

The full equation[1] is:

    E^2 = (pc)^2 + (m0 c^2)^2
...where p is momentum, and m0 is rest mass (mass in the rest frame of the object.)

[1] https://en.wikipedia.org/wiki/Mass%E2%80%93energy_equivalenc...

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