Constant acceleration question

AI Thread Summary
To achieve a speed of 0.51C in three days, the required constant acceleration was initially calculated as 120 m/s². The time conversion was incorrectly stated as 36 hours instead of the correct 72 hours for three days. The speed calculation also had an error, as it should reflect 0.51C rather than 0.051C. Participants in the discussion pointed out these mistakes and emphasized the importance of accurate conversions and calculations. The conversation highlights the need for careful attention to detail in physics problems.
DawnJohn
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Homework Statement


An interstlear ship has a mass of 8.97 kg x10^6 and is initially at rest to a star system. What constant acceleration is needed to bring the ship up to a speed of 0.51C, relative to the star system in three days.

Homework Equations



constant acceleration = v2-v1/t2-t1

The Attempt at a Solution



a=1.5x10^7/1.3 x 10^5
a=120 m/s^2?

Help!
 
Last edited:
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Can you show how you got the numbers you used?
 
Constant acceleration numbers...

the numbers I used were:

Time is 3 days (posted in question)=36 hours=2160 minutes = 129 600 or 1.3 x 10^5
Speed is .051c (c=3.0 x 10^8) .051 x 3.0 = 1.5 x10 ^7

I'm not sure if this is the correct way to be approaching this question? Any help would be greatly appreciated=)
 
Done right, but with a lot of mistakes. Check your math:

3 days =/= 36 hours.
 
OK, in your original post you have it as 0.51c so I didn't get the same number. Also, there are 24 hrs in a day, not 12. So it would be 72 hrs for 3 days.
 
Oops, I've been doing this way to long...thanks for pointing that out, I think my brain is turning to mush! I'll try again, thanks for your help!
 
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