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A sound wave travels from air to water. The angle of incidence is alpha_1, and the angle of reflection is alpha_2. If the Snell.s law is valid, then ...... |
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Answer» `alpha_1 = alpha_2` Angle of reflection r = `alpha_2` Here Snell.s LAW will be obeyed. `therefore n_A sin alpha_1=n_w sin alpha_2` `therefore (sinalpha_1)/(sin alpha_2)=(n_w)/(n_A)`….......(1) Now `(n_w)/(n_A)=(C//v_w)/(C//v_A)=(v_w)/(v_A) lt 1` `v_A lt v_w` .......(2) (The velocity of sound in WATER is more than th velocity of sound in air) From equation (1) and (2), `(sin alpha_1)/(sin alpha_2) lt 1 = sin alpha_1 lt sin alpha_2` `therefore alpha_1 lt alpha_2` (sin function is increasing function) |
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