A Twin Paradox Question, totally lost.

  • #1
Engineergirl2
7
0

Homework Statement



Planet W is 12ly from earth. Anna and Bob are both 20 years old. Anna travels to planet W at 0.6c, quickly turns around, and returns to earth at 0.6c. How old will Anna and Bob be when Anna gets back?



Homework Equations





The Attempt at a Solution



I've tried so many things and nothing is working. Apparently Bob is 60 years and Anna is 52 years. I'm completely lost on the idea of twin paradoxes, I could use some serious help. Thank you!
 

Answers and Replies

  • #2
voko
6,054
391
Can you see why it is 60 years for Bob?

For Anna, the distance to W and back is Lorentz-contracted.
 
  • #3
Engineergirl2
7
0
B/c 24cyrs/0.6c is equal to forty. Therefore you add them and get 60. Then, Anna is 52 years because the total distance that she appears to travel is 19.2? And 19.2cyrs/0.6c is equal to 32. add that to20 and you get 52. I ended up using length contraction. Sorry that was actually pretty easy!
 

Suggested for: A Twin Paradox Question, totally lost.

  • Last Post
2
Replies
50
Views
509
  • Last Post
Replies
2
Views
249
  • Last Post
Replies
17
Views
885
Replies
2
Views
540
Replies
23
Views
339
  • Last Post
Replies
11
Views
293
Replies
0
Views
265
Top