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Projectile Launch - Using Earth's Radius

  • Thread starter bustin
  • Start date
  • #1
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1. What is the launch speed of a projectile that rises vertically above the Earth to an altitude equal to 14 Rearth before coming to rest momentarily?



Homework Equations




sqrt{2GM(\\frac{1}{R_e}-\\frac{1}{14R_e})}

The Attempt at a Solution



G= 6.67x10^11
M=5.97x10^24
R_e=6.37x10^6

I get 2988 m/s I know its wrong but I gave it a shot. This is for online homework. Any help would be very nice. Thanks in advance
 

Answers and Replies

  • #2
D H
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What is the total mechanical energy at launch? At maximum altitude? How do these relate?
 
  • #3
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i tried to look into that but I couldn't find much info in my book. could you be more specific?
 
  • #4
5
0
i finally got it. i got 10802 m/s.

thanks for the tip
 

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