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A wave is changing from medium A to medium B and it travels slower in medium B than in medium A. If I draw a normal line from the boundary to the wavefront the wavefront in medium B will move away from the normal? I attached to make it more clear

Furthermore, I got this question:

The angle between the wavefronts and the interface in region A is 60. The refractive index_{a}n_{b}is 1.4.

What I did was: if 60 between wavefront and boundary, 30 degrees between ray and boundary: sin 30 / sin r = 1.4. I then got between the wavefront and the boundary 69.1 degrees but it is wrong, the mark scheme got 38 degrees. Can anyone help me?

Thanks

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# Homework Help: Reflection and Wavefronts

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