Rainbow
When sunlight enters a raindrop, it is refracted along its path, causing different wavelengths of white light.
So the one with higher wavelength (red) bends the least while the one with lower wavelength (violet) bends the most.
After this, these component rays hit the surface inside the drop and if the angle between the normal and the refracted ray on the drop surface becomes more than the critical angle (48°), then the light gets reflected inside the drop itself. This reflected light is refracted again as it exits the drop.
So it is found that violet light is emitted at an angle of 40° and red light is emitted at an angle of 42° with respect to the light ray coming from the Sun. The values of the angles for the wavelengths of other colors lie between the red and violet wavelengths.