True: The frequency of light is determined by its source. Different light sources emit light with different frequencies, which determine the color and properties of the light.
True: X-rays are absorbed by bone due to their higher density and calcium content compared to other tissues in the body.
False: The index of light is not the ratio between two wavelengths, it is the ratio between the speed of light in a vacuum and the speed of light in a particular medium.
True: The cornea is the transparent outer layer of the eye that protects the eye and helps to focus light onto the retina.
