• Support PF! Buy your school textbooks, materials and every day products Here!

Position Vector Problem

  • Thread starter bodensee9
  • Start date
178
0
1. Homework Statement
Suppose that the position function of a spaceship is r(t) = (3+t)i + (2+ln T)j + (7-4/t^2+1)k. Suppose you want the ship to coast to a space station located at (6.4.9). What time should you turn your engine off?


2. Homework Equations

r' = velocity. r" = acceleration.
3. The Attempt at a Solution

I guess when you turn the engine off there is no acceleration. So
|r"| = |<0,-1/t^2,(8(t^2+1)-16t^2(t^2+1)^4)/(t^2+1)^4| = 0. But I'm not really sure what to do after that or if this is even the right approach. Any suggestions? Thanks!!
 

Answers and Replies

Related Threads for: Position Vector Problem

Replies
1
Views
12K
Replies
7
Views
3K
  • Last Post
Replies
1
Views
5K
  • Last Post
Replies
4
Views
1K
  • Last Post
Replies
4
Views
466
  • Last Post
Replies
4
Views
4K
  • Last Post
Replies
8
Views
43K
Top