How much energy is needed for a spaceship to go from 0 to Mach 30 in under 10 seconds?

The Spaceship has a circumference of $20 ft$. A height of $6 ft$. It weighs $7,000 lbs$

We, humans, stole the design and created our own, but our copy-cat crumbles up under the intense mass increase due to the unbelievable time that hypersonic speeds are obtained.

How, strong would the Alien spaceship have to be to not crumble under extreme forces?


Is it okay too ask this question?

  • $\begingroup$ The question kinda loses meaningfulness with the alien-spacecraft specification anyway, as our laws of physics were designed to describe things we encounter in everyday life; they may be completely worthless in describing an advanced technology. I mean, sure, if we do see some alien spacecraft, let's try to make sense of it with whatever tools we've got -- just, don't expect things to work out that simply. $\endgroup$
    – Nat
    Commented May 4, 2020 at 10:47

1 Answer 1


There's no need to mention the UFO stuff. However, the question is off-topic, because calculation questions like that are homework-like.

  • 2
    $\begingroup$ BTW, Mach 30 isn't a relativistic speed, and anyway relativistic mass is a deprecated concept. OTOH, pulling 105 $g$ is going to be tough on any craft (and its occupants), especially in the lower atmosphere. ;) $\endgroup$
    – PM 2Ring
    Commented May 2, 2020 at 1:36
  • $\begingroup$ Tough. Ask and you shall receive the opposite! $\endgroup$
    – The T
    Commented May 3, 2020 at 0:53

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