A transparent rectangular block 5.0cm thick is placed on a black dot. The dot when viewed from above is seem 3.0cm from the top of the block calculate the refractive index of the material of the block.
The velocities of light in air and glass are 3.0 x10\(^8\)ms\(^{-1}\) and 1.8 \(\times \)10\(^8\) ms\(^{-1}\) respectively. Calculate the sine of the angle of incidence that will produce an angle of refraction of 30° for a ray of light incident on glass.
