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Unread 06-02-2017, 12:28
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FRC #0057 (The Leopards)
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Re: Poll: Reasonable and achievable, or shooting for the stars?

Quote:
Originally Posted by JesseK View Post
Besides, I don't think our FRC batteries have enough juice to get the balls into orbit, let alone beyond orbit.
18 Ah @ 12V = 12*18 Watt-hours * 60 min/hr * 60 s/min = 777600 Watt-s or Joules. Escape velocity is 11186 m/s. So 777600 = 1/2 * m * (11186)^2 = 12.4g. Balls weigh 70g, so you'd need 6 batteries charging your ball launching system to reach escape velocity. Not counting drag, etc. A properly designed charging system could probably send a penny into solar orbit, though.

EDIT: Wikipedia also tells me delta-v to Low Earth Orbit is 9.4km/s, so getting into orbit isn't any easier. Not to mention you need an onboard motor for a circularization burn. Unless you're using ground based lasers ablating your fuel as a "motor".
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Last edited by Kevin Sevcik : 06-02-2017 at 12:41.
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