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Homework Help: Rocket speed of light question

  1. Aug 25, 2005 #1
    A rocket ship in free space moves with constant acceleration 32 ft/sec^2. (a) If it starts from rest, how long will it take to acquire a speed one-tenth that of light? (b) How far will it travel in doing so?

    So we are given [itex] a_{x} = 32 \frac{ft}{sec^{2}} [/itex], and [itex] v_{x}_{0} = 0 [/itex]. One-tenth the speed of light is [itex] 1.86\times 10^{4} \frac{miles}{sec} [/itex]. For the first part would I use [itex] v_{x} = v_{x}_{0} + a_{x}t [/itex]? And for the second part I could use [itex] x = x_{0} + v_{x}_{0}t + \frac{1}{2}a_{x}t^{2} [/itex]

  2. jcsd
  3. Aug 25, 2005 #2

    Doc Al

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    Staff: Mentor

    If the acceleration is measured in [itex]f/s^2[/itex], then your speed must be measured in feet/sec, not miles/sec. (Do the unit conversion.) Other than that, your method looks good.
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