When light waves travel from rarer medium to denser medium, the qunatities which get changed are

Step-by-step solution

When light travels from one medium to another, the frequency of the light remains constant as it is a characteristic property of the source of light. The velocity of light changes depending on the refractive index of the medium, given by v = c . Since v = and the frequency is constant, the wavelength must also change proportionally with the velocity. Thus, velocity and wavelength change when light travels from a rarer medium to a denser medium. Answer: velocity and wavelength.