IB Physics: Reflection and Transmission / Refraction of Waves

IB Physics Topic 4.3
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Table of Contents
0:00 Introduction
0:08 Simulation of reflection of wave
2:14 Fixed and free barrier reflections
3:00 Effects of Change of medium on a wave
4:22 Two dimensional wave diagram
5:45 Refraction
9:36 Least time path for light
10:45 Axis analogy
11:46 Applications of refraction: Desert mirage and imaginary Highway puddles
13:28 Summary

[coolkid]

How do you know if something is a free barrier or a fixed barrier?

[pc_gamer]

Isn't the fixed barrier scenario in 2 dimensions? Because you have an upwards and sideways displacement?

[harryyoon]

are pulse reflections still in the 2016 IB physics syllabus?

[vivindeena]

i dont see the "Good portion that gets reflected back
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