1Water, alcohol, kerosene oil, glycerin, glass and diamond have refractive indices of 1.33, 1.36, 1.44, 1.47, 1.50 and 2.42, and light travels through them at 2.25, 2.19, 2.08, 2.04, 2.00 and 1.24 × 10⁸ m/s in that order. What can be concluded from the increasing order of refractive index and the decreasing order of the speed of light in these media?
2For \( i = 15^\circ \) and \( r = 10^\circ \), find \( \sin i \), \( \sin r \) and \( \frac{\sin i}{\sin r} \).
3A light beam is passed through the flat face of a semicircular glass slab at different angles of incidence and the angles of refraction are measured. After the calculations, what conclusion is drawn?
4State the two laws of refraction of light.
5Define refractive index in two ways.
6Why is a semicircular slab, rather than a rectangular one, used to check the laws of refraction?
7Why does refractive index have no unit?
8The refractive index of glass is 1.5. What is the speed of light in glass?
9Light enters water from air at an angle of incidence of 60°. If the refractive index of water is 1.33, what is the angle of refraction?
10At the same angle of incidence, does light bend more going from air into glass or from air into diamond? Why?