Refraction of waves

The diagram below shows plane wavefronts incident on a boundary between two media


A and B. 

 
 
 
  The ratio

refractive index of medium B/ refractive index of medium A           is 1.4.

The angle between an incident wavefront and the normal to the boundary is 50

.
(ii) On the diagram above, construct three wavefronts to show the refraction of the


wave at the boundary.



(i) Calculate the angle between a refracted wavefront and the normal to the boundary.

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