where \({\theta}\) is measured anti-clockwise from the positive \(x\)-axis. As the point P moves anti-clockwise round the circle from (1, 0), the angle \(\theta\) increases until P returns to its ...

{sin\theta _{2}}\) When you use this relationship, angle \(\theta _{1}\) must always be the angle in a vacuum (or air). Refractive index depends on the frequency or colour of light. Light of ...