Physics
In the given diagram, two transparent optical media are shown. The rarer medium is air, while the denser medium is water. Redraw the diagram by showing the paths of the rays after striking the surface of separation AD for the incident rays OA, OB, OC and OD, respectively. (Critical angle for the denser medium = 48°)
Answer
(a) The ray OA will go straight without any deviation, because angle of incidence is zero.
(b) The ray OB, after striking the surface of separation, will move away from the normal, because angle of incidence is less than critical angle and ray is going from denser to rarer medium
(c) The ray OC, after striking the surface, will graze along the surface, because angle of incidence is equal to critical angle.
(d) The ray OD will return back to the same denser medium. We will see total internal reflection because angle of incidence is greater than critical angle. (Note- It is necessary to show the angle of reflection as 60°)
Related Questions
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(b) Which two pairs of angles remain the same during the experiment?
(c) If the same experiment is performed first with red and then with blue light, which colour will suffer greater lateral displacement?
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(a) What does the portion AB represent?
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