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Question
Using Huygens’s construction of secondary wavelets draw a diagram showing the passage of a plane wavefront from a denser to a rarer medium. Using it verifies Snell’s law.
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Solution
AB: Incident Plane Wave Front and CE is Refracted Wave Front.
`sini = (BC)/(AC)` and `sinr = (AE)/(AC)`
`(sini)/(sinr) = (BC)/(AE) = v_1/v_2` = constant

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