Question
How is a wavefront defined? Using Huygen’s construction draw a figure showing the propagation of a plane wave refracting at a plane surface separating two media. Hence verify Snell’s law of refraction.
✓
Answer
- A surface of constant phase/A locus of points which oscillate in same phase.
- $\sin\text{i} = \frac{\text{BC}}{\text{AC}}$
$\sin\text{r} = \frac{\text{AE}}{\text{AC}}$
$\therefore \frac{\sin\text{i}}{\sin\text{r}} = \frac{\text{BC}}{\text{AE}}$
$ = \frac{c_1\text{t}}{c_2\text{t}} = \frac{c_1}{\text{c}_{2}} = n =\text{ constant}$
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