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Homework Help: Time dilation/related rates

  1. Nov 4, 2015 #1
    1. A spacecraft going at .99c is heading straight towards a star that's at a distance of 60,000 light years. Another ship 25,000 light years below the first one also is heading towards the star also at .99c. What what is the related rate between the time dilation of the first space craft to distance traveled at a time when both craft have traveled for 40 years in the time they experience.

    2. The time dilation equation of To*((1-(v^2/c^2))^-.5)-To=TD
    Where To is the time observed inside the space craft, v the velocity of the craft in terms of c(like .3c), c is the speed of light, and TD is time dilated, and or extra time outside of the space craft.

    3. I assume you'd take the derivative of the time dilated with respect time so it would be To*((1-(v^2/c^2))^-.5*(c^2*2v*dv/dt))+1*dt/dt*(1-(v^2/c^2))^-.5+-dt/dt. This however I know is completely wrong since time To is already in terms of time, that doesn't make anysense, and then how could you relate this to the distance traveled of the other craft? I really do need help.
    This belongs more in cal than in physics so I switched it.
  2. jcsd
  3. Nov 6, 2015 #2


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    Staff: Mentor

    There is no acceleration, the derivative with respect to velocity does not matter.
    I don't understand the grammar here, is that a translation?
    Also, what does "below" mean in space?

    Did you draw a sketch?
  4. Nov 6, 2015 #3

    Mister T

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    Gold Member

    Please check what you've typed against what you intended to type. They can't match.
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