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

Group velocity

  • Thread starter magnifik
  • Start date
360
0
given: E(k) = 2.5 x 10-28 k2 Joules
k = 5.8 x 109 m-1

Find the group velocity.

i know that the equation for vg = 2pi/h (dE/dk)
dE/dk = 2(2.5 x 10-28) = 5.0 x 10-28 k
plugging in k, i get
dE/dk = 2.9 x 10-18 J/m
vg = 2.75 x 1016 m-1 s-1

what i am more concerned about here is the fact that my units should be m/s (or at least i think so), not 1/m-s. can anyone tell me why i'm getting the wrong units?
 

Related Threads for: Group velocity

  • Last Post
Replies
1
Views
903
  • Last Post
Replies
1
Views
8K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
1
Views
4K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
0
Views
665
  • Last Post
Replies
3
Views
960
Top