A plane wave y = a sin [w (t-x/v)] undergo a normal incindence in a plane boundary seperating medium M₁ and M₂ and splits into a reflected and trasnmitted wave having speeds v₁ and v₂. Then the relation between v₁ and v₂ is:
a) v₁ = v₂
b) v₁ > v₂
c) v₁ < v₂
d) Relationship cannot be determined