For hearing the loudest ticking sound heard by the ear, find the angle x in the Fig.12.4.

From the given figure,

We get, Angle of incidence = Angle of reflection


Thus, 50o + x + x + 50o = 180o


2x + 100o = 180o


2x = 180o – 100o


2x = 80o


x = 40o


Therefore, Angle of reflection = 40o


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