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magnifik
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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?
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?